#### NATIONAL ELECTRICAL SUPPLY CO. v. THE UNITED STATES

[No. C-38.

Decided February 20, 1928]

*On the Proofs*

*Infringement of patent; transmitting apparatus for wireless telegraphy.*— Letters Patent No. 1145066, for transmitting apparatus for wireless telegraphy, issued on July 6, 1915, to plaintiff as *618assignee of Albert H. Johnson, *held*valid, and infringed by the United States as to claims 1, 4, 6, 7, and 8 thereof.

*Sarnie; design for easing for wireless telegraph generator.*— Designs Letters Patent No. 48638, for a casing for wireless telegraph generator, issued on February 28, 1916, to plaintiff as assignee of Albert H. Johnson, *held*invalid for want of ornamentality.

*Same; similar illustration in prior patent.*— An illustration in a prior patent showing similar arrangement of parts is not anticipatory where such an arrangement, read in connection with the inventor’s specifications and claims, accomplishes a different purpose and the essential thing relied on in the later patent is nowhere disclosed in the first.

*Same; experimental and public uées; seo. J/9&0, R. S.*— Where a sale is made of a device, without profit, solely with a view to perfecting it through experimentation by the vendee, which results in its perfection by the inventor, and no other sales are made or attempts to put it on the market, the use so made of the device is experimental and not public within the meaning of section 4920, R. S.

*The Reporter’s*statement of the case:

*Mr. O. L. Parker*for the plaintiff. *Mr. E. F. Oolladay*and Oolladay, *Clifford db PetPm*were on the brief.

*Mr. Melville D. Gfmrch,*with whom was *Mr. Assistant Attorney General H&t'mxm J.*Galloway, for the defendant. *Mr. Ha/rry E. KniffM*was on the brief.

The court made special findings of fact, as follows:

I. The plaintiff, National Electrical Supply Company, is a corporation organized under the laws of the State of Virginia, and has its principal office and place of business in the city of Washington, D. C.

II. In the winter of 1909-10 the Navy Department, desiring to secure portable wireless telegraph sets which would meet the requirements of the naval service, requested the plaintiff to try to build a set embodying a five-hundred-cycle alternating-current generator. In accordance with this request the plaintiff had its superintendent (A. H. Johnson) design and build such a machine, which was known as a motor generator.

As the result of the production of this machine, after some experimental work and a test, a requisition was issued by the Navy Department, under date of April 1, 1910, without *619advertisement, for five portable wireless telegraph (battleship) sets at $400 each, the plaintiff receiving $2,000 in payment thereof from the Navy Department. The requisition included the following phraseology: “ This is experimental material and can be supplied by this company and no others. It has been developed under the bureau’s direction.” These five sets, which were subsequently referred to as “ experimental sets, pure and simple,” by George H. Clark, expert radio aid of the Navy Department, were submitted to shop tests by plaintiff in order to determine the electrical and mechanical features of the sets, and then were sold unconditionally to the Navy Department at the above price, with no profit and at a loss to the plaintiff.

These five sets, each of which was entirely contained in a rectangular case 22% " x 15" x 10", were delivered to the U. S. S. *Montana,*at Norfolk, Virginia, by plaintiff on or about April 8 or 9,1910, for the purpose of testing these sets under service conditions. These sets included in their construction a motor generator set designed to be plugged in or connected with the battleship’s power supply so as to transform the electrical energy available on the ship into the particular form of electrical energy necessary for utilization in the radio-transmitting equipment.

More specifically stated, this motor generator or machine was composed of a bed plate or frame, supporting an alternating-current generator and a direct-current motor. The armatures of the motor and generator were mounted upon a common shaft, which extended beyond the bearing at the motor end, and which had mounted thereon a combined flywheel and fan, the function of the flywheel being to store up energy during the periods of nondelivery of current to the transformer of the wireless set, and to help out the motor by the use of such stored energy during the periods of current demand.

Fig. 1 of the appendix to these findings represents diagrammatically the associated elements and circuits of this motor generator structure. In this drawing A represents the connection to the source of current, which is the ship’s generators; B a rheostat for starting the machine; C the commutator of the direct-current motor with its brushes for *620carrying the current into the armature winding L of the direct-current motor; D the field winding of the direct-current motor; E the field winding of the alternating-current generator; F the collector rings and brushes of the alternating-current generator; M the armature winding of the alternating-current generator which is connected with the collector rings; G the shaft upon which the direct-current and alternating-current armatures, commutator, and collector rings are mounted; H a combined fan and flywheel mounted on the extension of this shaft; I a transformer of the wireless apparatus with its leads connected permanently to the brushes bearing on the collector rings F of the alternator; K the sending key of the wireless set connected in series with the field winding E of the alternator and source of current A.

These five sets were tested on the IT. S. S. *Montana*under practical working conditions and found to have many defects in material. Many suggestions as to changes were made by the radio expert of the Navy Department in charge of these tests in his report, dated 8-2-10, and among these was the recommendation that, although “having the operating key in series with the alternator field proved very successful, though it does not make any difference in the speed regulation whether this method or the method of keeping the field constant, and putting the key in series with the brushes in use. It is therefore recommended that the latter method be adhered to in future, as the voltage delivered from the machine is more constant.”

It was also found that the sets failed to perform properly when operated in the Tropics through overheating and lack of ventilation.

The sets were subjected to tests for a period of three years, and during this time were frequently returned to the plaintiff’s factory for changes and modifications in mechanical details and refinements. No more changes were made.

The radio expert’s report concluded with the statement that the portable sets “ worked up to distances of 20 miles with perfect success, and the writer is now about to take up the question of furnishing small gasoline engines for driving units in order that the sets may be used in steam launches.”

*621III. Plaintiff was continually experimenting with the different wireless signaling apparatus and in the fall of 1911 furnished the Navy Department with four improved portable wireless telegraph sets which were put into experimental use for a period of two years and reported on from time to time and returned for refabrication to meet the requirements to which the 1910 sets could not measure.

IY. In August, 1911, Albert H. Johnson, superintendent of the plaintiff’s factory, first produced a hand-power generator adapted to function as a current supply for a wireless telegraph set. The electrical and mechanical characteristics of the machine were substantially identical with the form of machine diagrammatically illustrated in the drawing of Johnson’s patent No. 1145066 in suit.

In the first development or construction temporary use was made of one of the motor-generator sets that plaintiff was working on for the Navy Department. The circuit arrangements thereof were changed by removing the line wires and so connecting the direct-current end of the machine — i. e., the motor — that it would function as a generator and supply energy to the field of the alternating-current generator under the control of the key placed in the circuit between the generator and field.

A hand crank and gearing were added to rotate the common armature shaft which carried, as before, both armatures and the flywheel.

In December, 1911, plaintiff began and completed the construction of another machine of practically the same kind and having the same electrical details. This machine was mounted on a cast-iron frame and had a gear box also bolted to the frame, which gear box carried a shaft having crank handles thereon. This machine was incorporated in a portable wireless set and was delivered to the Navy Department in 1912 for the purpose of experimentation. As a result of satisfactory tests of the same, *17*hand-generator sets of this same pattern were purchased from plaintiff by the Navy.

Subsequently the hand-generator set was redesigned and the outer case was made into a more compact package, and many hundreds were then sold to the Army, Navy, and National Guard.

*622V. On November 14, 1912, Albert H. Johnson, a citizen of the United States, then a resident of the city of Washington, D. C., filed in the United States Patent Office an application for a “patent for the transmitting apparatus for wireless telegraphy,” upon which application was issued United States Letters Patent No. 1145066, dated July 6,1915, to the plaintiff, the National Electrical Supply Company, as assignee of the entire right, title, and interest to said apparatus and letters patent, which patent is as follows:

United States Patent Office

Albert H. Johnson, of Washington, District of Columbia, Assignor to National Electrical Supply Company, of Washington, District of Columbia, a corporation of Virginia. Transmitting apparatus for wireless telegraphy. 1145066. Specification of Letters Patent. Patented July 6, 1915. Application filed November 14, 1912. Serial No. 731382

*To all whom it may concern:*

Be it known that I, Albert H. Johnson, a citizen of the United States, residing at Washington, in the District of Columbia, have invented certain new and useful Improvements in Transmitting Apparatus for Wireless Telegraphy, of which the following is a specification.

This invention relates to certain new and useful improvements in transmitting apparatus for wireless signaling which, while adapted for general use in the art, are particularly valuable and important in their application to portable generating sets for wireless telegraphy.

An important object of this invention is to provide transmitting apparatus for wireless telegraphy which can be operated with the minimum application of power.

Another object of this invention is to provide a portable, manually operated, preferably self-contained generating set for wireless transmission which is light in weight, simple in construction, convenient to use, and capable of providing current for wireless communication throughout a wide area.

Other objects and advantages of this invention will be apparent from the following specification wherein reference is made to the accompanying drawings showing, for purposes of illustration, a diagrammatic view of transmitting apparatus and circuits thereof involving my invention.

*623cfovue-wtoi *j!Z&ert:JikJohnsfi^**» V-y^CA. Gtiowww (sy (ynwJk*^vlv^( A. H. JOHNSON. TRANSMITTING APPARATUS POR WIRELESS TELEGRAPHY. APPLICATION FILCO NOV. 14, 1912. 1,145,066.. Patented July 6,1915. *rr ys>*

*624In the drawing, 1 represents the armature winding of a generator or exciter 2, preferably a shunt wound direct current generator or exciter, having brushes 3 and 4 separately connected in parallel as shown with the field 5 of the exciter 2 and with the field 6 of a generator 7, preferably an alternating current generator, whose armature 8 is mechanically connected by the shaft 9 with the armature 1. The armature windings 1 and 8 are preferably wound upon the same armature shaft. A transmitting key 10 is included in circuit with the armature winding 1 and the field 6.

The brushes 11 and 12 of the generator 7 are connected, as shown, with the primary winding 13 of a transformer 14. The ends of the secondary winding 15 of the transformer 14 may be connected respectively with the aerial conductor A and with the earth connection E, these conductors being in electrical communication with the spark gap 16, in accordance with the usual practice.

The shaft 9 carrying the armature windings of the generators 2 and 7 may be rotated by any suitable means. In the preferred form of my invention the shaft 9 is manually operated by means of the cranks 17 and 18 mounted upon the ends of a suitably supported shaft 19 which may carry a large sprocket wheel 20, power being supplied to a small sprocket 21 on shaft 9 by means of a sprocket chain 22, Each crank is designed and arranged to be operated by one or more men. Mounted upon the armature shaft 9 is a fly wheel 23 which in my invention serves the important purpose of storing up energy when the transmitting key 10 is open, and the shaft 9 accordingly capable of being easily rotated, and giving out energy when the transmitting key 10 is closed and the armature shaft requires more power to effect its rotation.

The method of operation of my apparatus is as follows:

The armature shaft 9 being rotated by any suitable means, preferably manually, by the operation of the cranks' 17 and 18, current is generated in the armature winding 1 and its field 5 is energized. When the transmitting key 10 is open there is no circulation of current from the exciter 2 through the field 6 of the generator 7 and, consequently, little resistance is offered to the rotation of the armature 8. The shaft 9 is relatively easily rotated and considerable energy may be stored up in the flywheel 23. When the transmitting key 10 is closed the field 6 of the generator 7 is energized and a suitable current generated in the armature 8, which pas’ses from brush 11 through the primary coil 13 of the transformer. 14 back to the brush 12. As the resistance of the rotation of the shaft 9 increases greatly when the key 10 is *625closed and the field 6 energized the kinetic energy stored up in the revolving flywheel is utilized to take care of this sudden increase of resistance or drag and as the key is' only closed when messages are being sent and then only for short periods of time it is possible for men laboring at the cranks *17*and 18 to keep the shaft 9 rotating approximately uniformly at a speed, while the apparatus is in use, which they could not maintain if the field 6 were energized continuously instead of intermittently as described. It will therefore be apparent that by my improvement it is possible to secure a materially greater range of wireless communication from power exerted by men laboring at the operating cranks than would otherwise be possible.

While I have shown and described the preferred form of my apparatus it is to be understood that numerous changes, may be made in the form and details of construction without departing from the spirit of my invention or the scope of the subjoined claims.

Having described my invention, I claim—

1. In transmitting apparatus for wireless signaling, an alternating current generator to supply the transmitting current, a direct current generator adapted and arranged to supply current to the field of the alternating current generator, a transmitting key in circuit with the direct current generator, and the field of the alternating current generator whereby the field of' the alternating current generator is energized by the direct current generator only when the key is closed, the armature windings' of both generators being mounted upon the same armature shaft, and means for storing up surplus energy imparted to the shaft when the key is open and imparting it to the shaft when the key is closed whereby the armature shaft may be operated at a substantially uniform speed from a small energy source.

2. In transmitting apparatus' for wireless signaling, an electric generator, a separate source of current adapted to energize the field of said generator, a transmitting key between the said field and the source of current and a flywheel fixed upon the armature shaft of the generator adapted to store up excess energy imparted to the shaft when the key is open and to impart it to the shaft when the key is closed whereby the armature shaft may be operated at a substantially uniform speed from a small energy source.

3. In transmitting apparatus for wireless signaling, an electric generator, a separate source of current adapted to energize the field of said generator, a transmitting key between the said field and the source of current, a flywheel fixed upon the armature shaft of the generator adapted to *626store up excess energy imparted to the shaft when the key is open and to impart it to the shaft when the key is closed, and manually operable means to rotate the said armature shaft.

4. In transmitting apparatus for wireless signaling, an electric' generator to supply the transmitting current, an electric generator adapted and arranged to act as an exciter for the first-named generator, the armature of the exciter being connected in parallel with the fields of the exciter and transmitting generator, a transmitting key in circuit with the field of the transmitting generator, common manually operated means to effect the rotation of the armatures of the exciter and transmitting generator, and means for storing up energy from such rotation means when the transmitting key is open and utilizing it in the rotation of the armatures when the key is closed.

5. In transmitting apparatus for wireless signaling, an electric generator to supply the transmitting current, an electric generator or exciter adapted and arranged to supply current to the field of the transmitting generator, a transmitting key in circuit between the said field and the exciter whereby the said field is energized by the exciter only when the key is closed and means for storing up surplus energy imparted to the shaft of the exciter when the key is open and imparting it to the shaft when the key is closed whereby such armature shaft may be operated at a substantially uniform speed from a small energy source.

6. In transmitting apparatus for wireless signaling, an electric generator to supply the transmitting current, an electric generator adapted and arranged to act as an exciter for the first-named generator, a key in circuit between the exciter and the transmitting generator, common manually operated means to effect the rotation of the armatures of the transmitting generator and exciter, means for storing up surplus energy imparted to the armature of the exciter when the key is open and imparting it to such armature when the key is closed whereby such armature may be operated at a substantially uniform speed from a small energy source.

*1.*In transmitting apparatus for wireless signaling, an electric generator to supply the transmitting current, an electric generator or exciter adapted and arranged to supply current to the field of the transmitting generator, a transmitting key in the circuit between the said field and the exciter whereby the said field is energized by the exciter only when the key is closed, the armature windings of the two generators being mounted upon the same armature shaft, and means for storing up surplus energy imparted to the said shaft when the key is open and imparting it to said *627shaft when the' key is closed whereby the said shaft may be operated at a substantially uniform speed from a small energy source.

8. In transmitting apparatus for wireless signaling, an electric generator to supply the transmitting current, an electric generator or exciter adapted and arranged to supply current to the field of the transmitting generator, a transmitting key in the circuit between the said field and the exciter whereby the said field is energized by the exciter only when the key is closed, the armature windings of the two generators being mounted upon the same armature shaft, and a flywheel fixed upon the said shaft whereby, when signals are being sent, the armature shaft may be operated at a substantially uniform speed from a small energy source.

9. In transmitting apparatus for wireless signaling, an alternating-current generator to supply the transmitting current, a direct-current generator adapted and arranged to supply current to the field of the alternating-current generator, a transmitting key in circuit with the direct-current generator and the field of the alternating-current generator whereby the field of the alternating-current generator is energized by the direct-current generator only when the key is closed, means to effect the rotation of the armatures of the alternating-current and direct-current- generators and means for storing up surplus energy imparted to the armature shaft of the alternating-current generator when the key is open and imparting it to the said shaft when the key is closed, whereby the armature of the alternating-current generator may be rotated at a substantially uniform speed from a small energy source.

In testimony whereof I affix mjr signature in presence of two witnesses.

Albert H. Johnson.

Witnesses:

Henry B. DeGroot,

Chas. O. Beed.

YI. With respect to Patent No. 1145066, plaintiff in this action limits his right to recover to the alleged use by the United States, without his consent, of the invention as defined in claims 1, 4, 6, 7, and 8.

VII. The special features of the invention as defined in the above claims relate to a generator structure for wireless telegraphy comprising an alternating-current generator .and direct-current generator functioning to supply field excitation to the alternating-current generator, a key in the circu.it *628between the field of the alternating-current generator and the brushes of the direct-current generator, a flywheel or energy-storing means, and means for operating the generators at a substantially uniform speed.

As defined in claims 1, *6,1,*and 8, this means is defined as “ a small energy source.” As defined in claims 4 and 6, this means is defined as *“*common manually operated means ” to effect the rotation of the armatures of the transmitting generator exciter and the transmitting generator. The special features of this generator as defined in claims 1, 4, 6, 7, and 8 are:

The structure is such as to permit the required electrical energy to be derived from the hand drive, thus avoiding-carrying into the field of operation undesirable and burdensome sources of energy such as storage batteries.

With the key in the circuit between the exciter and the alternating-current generator, instead of in the output circuit, during the period of time the key is open there is a saving of field current, which represents the total output of the exciter, and in addition there is a saving of energy due to the absence of a magnetic brake effect on the alternating-current armature which is present when an armature rotates in a magnetic field.

The key being in the circuit between the exciter and the alternating-current generator field, this circuit is left open when not actually sending messages, and during the sending of messages, i. e., during the intervals between the dots and dashes, this circuit is open about 55 per cent of the time.

If the key were in the output circuit, and the field of the alternating-current generator were thus kept continuously excited, additional energy sufficient to supply the field current and to overcome the magnetic brake effect on the alternating-current armature would be continuously needed. With only a small energy source more output is therefore available with the key in the field circuit than would be the case with the key in the output circuit. This is also due in part to the means for storing up energy, ,i. e., the flywheel, during the periods the key is open.

The armature shaft may be operated at a substantial uniform speed from a small energy source.

*629In a hand-power generator having a construction similar to the patent in suit, with the key open, the generator could be turned very easily with one hand. If the key was held down continuously, four men, or as many as could get around the machine, could not keep it up to speed. But with an intermittent load of dots and dashes, four men could very easily send a message as long as they wished to send.

VIII. Patent No. 749435, dated January 12, 1904, was issued to Lee De Forest, in which a gasoline engine was used as the motive power for the alternating-current generator of a portable radio transmitting set. The key was located in the output circuit of the generator.

Patent No. 756720, dated April 5, 1904, was issued to Harry Shoemaker. Two forms of structure are disclosed; in the first form a high-potential direct current is produced by three dynamo-electric machines with their armatures connected in series. The fields of these machines are energized from a source of energy shown as a battery, and the key is in the circuit between this source of energy and the fields of the dynamo-electric machines or generators; in the second form the high-potential direct current is produced by storage batteries.

The Shoemaker patent was cited by the Patent Office during the prosecution of the Johnson application and prior to the interference proceeding, and certain amendments were made to the claims to distinguish from the Shoemaker disclosure.

Neither the De Forest nor the Shoemaker patents disclose a generator operated by manual power or by any small energy source, nor one in which the field circuit in which the key is disposed receives the current produced by the rotation of the generator armature and variable with the speed of such rotation.

In “ Modern Polyphase Machinery,” published at London in 1906, several excerpts show the provision of direct-current exciters for the fields of alternating-current generators, the mounting of the armature windings of such exciters on the same shaft with the alternating-current armature and provision for flywheel action for alternating-current gener*630ators. In these excerpts no reference is made to hand operation or to wireless telegraph apparatus.

IX. A. H. Johnson, on September 23, 1915, filed in the United States Patent Office a certain design for a casing for the generator for wireless telegraph upon which application there was granted United States Designs Letters Patent No. 48638, dated February 28, 1916, to the plaintiff as assignee of the entire right, title, and interest of Johnson.

X. Neither Johnson nor the plaintiff was in the employ or service of'the United States at the time he made the invention and design or when the patents were granted. The plaintiff is now and has been the sole and exclusive owner of both patents since their grant.

XI. On the 4th of June, 1917, the Chief Signal Corps Officer of the United States Army, by order No. 8079, caused to be made by the General Electric Company, situate at Schenectady, N. Y., one complete set of drawings, patterns, and tools necessary to manufacture radio hand-power generators which should be duplicates of a sample generator then in the possession of the said General Electric Company, the sample being a hand-operated generator manufactured in accordance with Letters Patent No. 1145066 and having a casing identical in appearance with the design patented in design patent No. 48638, such sample being one of a number of generators made for and sold by the plaintiff to tho United States Government for use in the Signal Corps of the United States Army.

XII. On the 18th day of September, 1917, the Chief Signal Officer, United States Army, under order No. 10385, caused to be manufactured by the General Electric Company 250 hand-operated generators (without speedometers) in accordance with the drawings and patterns furnished by the company under order No. 8079 of June 4, 1917, for the sum of $355 per set, and at the ¿same time the said Chief Signal Officer ordered additional tools, jigs, and dies for the manufacture of the generators for the sum of $1,000.00.

XIII. The generator sets manufactured pursuant to order No. 10385 were delivered to and used by the Signal Corps of the United States Army. The manufacture and use were without the license or consent of plaintiff.

*631XIV. One of the hand-power generators manufactured pursuant to order 10385, as indicated by the following identification marks thereon:

“ Model 1915 radio hand generator made for the Signal Corps, United States Army, by the General Electric Co., No. 698, Order No.

10385, 1911, General Electric Co., No. 836698, N-P 16624,”

was found- to embody a casing identical in appearance with that illustrated in design Patent No. 48638, and to have located therein a shaft operated by cranks and a gear train, which shaft carried a flywheel, a direct-current armature, and an alternating-current armature. These two generators

The field winding of the direct-current machine was connected with the brushes of the direct-current armature. The field winding of the alternator was connected with the brushes of the direct-current machine, with a plug terminal inserted in one lead for the incorporation of a key in this circuit.

The alternating-current armature was connected through slip rings, brushes, and conductors to a plug connection adapted to receive the terminals of conductors leading to the primary winding of the radio transformer.

XV. On the 12th day of January, 1921, a claim for $17,000 was made to the Secretary of War and by him referred to *632the Interdepartmental Radio Board, and an award of $8,875 was made on the 12th of March, 1921, but was not accepted by or paid to plaintiff. No action has been had before Congress.

Booth, Judge,

delivered the opinion of the court:

Albert H. Johnson, on November 12, 1912, filed in the Patent Office an application for a “ patent for transmitting apparatus for wireless telegraphy.” Letters Patent No. 1145066 were duly issued upon the application to the plaintiff company, assignees of Johnson, July 6,1915. On September 23, 1915, Johnson filed another application for a design patent embodying a casing for the generator of wireless telegraphy, on which application the plaintiff, as assignee of Johnson, secured Letters Patent No. 48638 on February 28, 1916. The petition asserts the liability of the Government as an infringer under claims 1, 4, 6, 7, and 8 of patent No. 1145066, both patents being involved. The origin of the claim is traceable to a desire of the Navy Department in the latter part of 1909 and the first of the year 1910 to obtain wireless telegraph sets which would meet Navy requirements. To accomplish the purpose, plaintiff was requested to attempt the construction of a wireless set “ embodying a five-hundred-cycle alternating-current generator.” The plaintiff did design and construct such a machine; i. e., Mr. Johnson, plaintiff’s superintendent, did the work. The machine so designed was necessarily experimental in character, and subsequent to tests, the Navy Department, on April 1, 1910, issued a requisition for five sets of the Johnson type, which were duly furnished and paid for at the price of $400 each. The purchase was made without advertisement, and the requisition for the article purchased contained these significant words: “ This is experimental material and can be supplied by this company and no others.” The findings disclose that the sale was made without profit to the vendor. The five sets were installed on board the TJ. S. S. *Montana*on or about April 9, 1910, for the purpose of test and use. Numerous defects in material were discovered, and numerous changes were ma de upon the suggestions of both parties. The sets did not respond favorably in the *633Tropics; overheating and lack of ventilation retarded their efficiency. Finally, after frequent return of the sets to the plaintiff for changes and modification, they were found to be satisfactory and sufficiently powerful to transmit wireless messages within a radius of twenty miles. Three years of time was consumed in perfecting the apparatus to this favorr able point. A diagrammatical illustration of one of the sets appears in the appendix to the findings.

The patentee’s conception in this respect was embodied in a machine composed of a bedplate or frame upon which rested an alternating-current generator and a direct-current motor. The armatures of the motor and generator were mounted upon a common shaft, extended beyond the bearing at the motor end, upon which there was mounted a combined flywheel and fan. The flywheel functioned to store up energy during periods of nondelivery of current to the transformers of the wireless set and obviously served to assist the motor during periods of current demand. The original source of electric current was the ship’s generators, a rheostat being employed to start or stop the machine. The sending key “ K ” was connected in series with the field winding of the alternating generator and the source of current “A.”

Without going more into specific detail, it is sufficient for the present to observe that two elements effective in the operation of the above machine appear in the source of power utilized to rotate the shaft upon which the motor and alternating current were mounted and in the placing of the operative key. Both play an important part in the disposition of the case. A machine, to meet the requirements of the Navy, had to possess features of distinctness in the form of compactness whereby they might be sheltered from destruction in the event of naval engagements by proper placement on board the ship, and certainty of operation in whatever climate the vessel might enter. Intercommunication with the ships in the fleet was the objective of the naval officers; to attain the purpose required a machine available both in peace and war times. Johnson, the original patentee of the latter machine, met the objective, and the first machine was a success. Success in the first attempt immediately suggested to the inventor the utilization of an apparatus for a *634similar purpose, available in the field or wherever to be used, capable of operation without reliance upon electric current from an independent source of power, differing from the first machines which were operated by *“*plugging in ” on the ship’s electric generators. Johnson’s idea was to attach to the machine a suitable apparatus, a manually operated source of power, thereby enabling the machine to function either on board a ship or in the field. In the language of the inventor, “ the invention is concerned only with the utilizing of such small energy to produce the maximum signaling range.” To attain the desired end involved more than mechanical skill.- It is true the elements the inventor had at hand and employed were old in the art; electric currents, electric generators, transformers, and intermittent key operations were well known as essential factors in transmitting electric energy. The opportunity for inventive genius in this respect was restricted within narrow limits. What could or could not be accomplished by electric mechanisms and the natural consequences flowing from the use of electric energy in the art of wireless telegraphy, so far as this record is concerned, offered little in the way of basic patents. Johnson’s first machine demonstrated the obvious fact that where the source of energy is continuous and powerful the magnetic drag occasioned by the constant energizing of the magnetic field of the alternating-current generator was a matter of small consequence. Likewise the location of the key for intermittent transmission caused no particular concern. What the inventor had to overcome if a manually operated machine was to prove successful was to minimize or remove the effect of the magnetic drag, a retarding force which effectually precluded the possibility of successful operation by man power.

It is conclusively established that the magnetic drag present in Johnson’s first machine was sufficient in extent to retard almost to the point of inefficiency the supplying of sufficient force to rotate the armature shaft upon, which the generators were mounted by the hand of man. What, then, did the patentee do ? This is best illustrated by the diagrammatic illustration in Finding V. In most respects the same construction employed in the first machine was again made *635available in the second machine. The vital distinction over the prior art, however, resides in the important fact that by an original conception Johnson did overcome the effect of the magnetic drag and made possible the supplying of energy by manual force; i. e., he utilized a “ small energy ” and did “ produce the maximum signaling range.” How was it done ? First, of course, was the attachment to the armature shaft of the flywheel “ 23,” operated by means of the cranks *“ 17*” and “ 18,” suitably supported by the shaft *“*19,” which carried the sprocket wheel “ 20,” power being supplied to a small sprocket “21 ”.on shaft “ 9 ” by means of a sprocket chain. The key “ 10,” which in the prior art was located in the output circuit, was in the new machine included in circuit with the armature winding “ 1 ” and the field “ 6,” with the result that when the armature shaft was rotated by the rotating device, manually operated, current is generated in the armature windings and the field “ 5 ” of the direct-current generator “ 2 ” energized; but the field “ 6 ” of the alternating-current generator “ 8 ” is not energized except during the times when the key “ 10 ” is closed, and, as admittedly true, the key “ 10 ” is closed approximate^ 45 per cent of the time, 55 per cent of the time is utilized by the manually operated device in storing up energy available as power when the key is closed and the magnetic drag tends to retard even and continuous flow of current.

The manifest difficulties of accurate description render an indispensable and constant reference to the illustrations lest the. real invention become obscured. Therefore it is especially essential to note that the patentee’s machine was1 the first in the field enabling the use of a small energy source to operate a portable wireless transmitting apparatus capable of producing .the maximum signaling range, and that this was accomplished by the utilization of elements old in the art, but employed in a new and novel way. It is not disputed that prior to the advent of the machine in suit operators at the hand device, with the alternating-current generator field “ 6 ” continuously energized, could not with a maximum of effort produce to exceed 200 watts of electric current. With the present machine a minimum of effort produces easily 300 watts, and, what is of vast importance, a continuous even *636flow essential to the effective transmission of dots and dashes. By the use of this machine the signaling range was increased .to 80 miles and it was found to be impervious to a change of climate. The experts of the Interdepartmental Radio Board tested the structure of the patent, carefully investigated its efficiency, and from current measurements reported that the patentee, by the single act of placing the key *“*10 ” in the field circuit instead of the output circuit “ K,” saved at least 20 per cent of the input energy, and that this saving accomplished “ greater distance of operation or longer operation of a lesser distance without changing operators.” Most significant in this connection is the testimony in the record that Johnson, in .the designing of his machine, applied the various elements at his command in a way contrary to the usual scientific formula, or the way and manner usually employed by those learned and skilled in the art. Again, the machine proved useful. It supplied a need, was recognized by the trade as conspicuous and valuable, and found a large and profitable market, as reflected in the number of sales made and demand therefor. The patentee’s claims, nine in number, cover the novelty of the invention and clearly disclose that the inventor did conceive the original idea of making available for radio transmission a compact, portable machine, capable of use wherever, a minimum of man power was available to turn the cranks “ 17 ” and “ 18 ” and rotate the armature shaft.

In the prior art two patents, one to Shoemaker, No. 756120, and another to De Forest, No. 749485, are cited as anticipatory of the patent in shit. In addition to the above patents excerpts from certain textbooks disclosing prior practice in electric-generator construction are insisted upon as conclusive. The Shoemaker patent was cited by the patent examiner during the prosecution by J ohnson of his application for patent and Johnson’s original claims were rejected thereon. Subsequently J ohnson presented to the examiner a statement pointing out in detail the distinct variance between the Shoemaker invention and his own, and the Patent Office reconsidered Johnson’s application, suggested certain amendments of claims, in the following language:

> *637“ Upon reconsideration claims 12 and 18 are allowed and claims 9 and 11 may be allowed if applicant will add at the end of these claims — whereby the armature shaft may be operated at a substantially uniform speed from a small-energy source. The Shoemaker patent clearly discloses all that applicant is claiming *except the idea of storing wp enough energy during the periods that the hey is open to permit the use of a source of power so> small that it Would oihemoise he vmamaüdble.*The claims which bring out this idea in connection with the specific apparatus us'ed are considered patentable.” (Italics are ours.)

Shoemaker’s conception was concerned with a radio-transmitting apparatus and not with the generator. There is nothing in the claims to anticipate the predominant idea of Johnson in utilizing a small energy source to operate the apparatus to attain the maximum signaling range. Shoemaker employed a relatively large current from an outside source to magnetize the field circuit and nowhere seems to have conceived the possibility of utilizing a minimum energy from a source attached to the machine itself. The placing of the key as shown was for the obvious purpose and function of satisfactorily controlling the high potential output produced by the plurality of generators in series and, as previously observed, the employment of great force to function the armature and set the machine ,in motion would, when used as used in the Shoemaker patent, render the magnetic drag quite unimportant. As a matter of fact, Shoemaker made no claim as to the location of the key, and clearly Shoemaker placed no reliance upon the key to function as Johnson designed it to function in making available a small source of energy. Observing the two patents in diagrammatical .illustrations, a first impression might well suggest a marked similarity; but when read in the light of their respective specifications and claims it is manifest that the two inventors were wide apart in their conceptions of a des,ired accomplishment. The plaintiff cites a case, *Gray*Telephone, *etc., Co.*v. *Baird Mfg. Co.,*174 Fed. 417, an excerpt from which is apropos:

“A patent for a mechanical combination is not anticipated by a drawing in a prior patent which incidentally shows a similar arrangement of parts, where such arrangement is *638not essential to the first invention, and was not designed,adapted, or used to perforin the function which it performs in the second invention, and where the first patent contains no suggestion of the way in which the result sought is accomplished by the second inventor.”

Of course, as many times said, and not infrequently refied upon, it is now easy to see how Shoemaker’s invention might with slight modification function as Johnson’s patent did function. The test, as uniformly sustained by the courts, is whether the prior patent was actually designed by the inventor to accomplish the identical purpose disclosed in the patent upon which it is cited as anticipatory. *Triumph Trap Co.*v. *Oneida Community Go.,*279 Fed. 142; *Toplif*v. Toplif, 145 U. S. 156; *Potts*v. *Greater,*155 U. S. 597.

Extensive comment upon the De Forest patent is, we think, unnecessary. De Forest does show a portable radio set; but it functions in a way that clearly demonstrates no conception of the employment of a small source of energy to obtain the largest scope of signaling.

The court has commented upon the fact that Johnson employed elements old in the art. Johnson has not disclaimed the fact. Textbooks are numerous pointing out the scientific operation of electric current and the precise manner in which it may be utilized to serve a designed purpose. New machines and novel devices are almost daily coming into existence taking extensive advantage of the knowledge published broadcast and easily obtainable. Of course direct-current exciters, alternating-current generators, flywheels, fans, sprockets, etc., mounted upon an armature shaft were old; but old as they were, they were not combined into a successfully operative device which could be made to function and obtain the highest possible result by the application of a minimum amount of energy supplied by the hand of man. The problem Johnson was dealing with was to discard the well-known and long-established fact that with an independent and powerful source of energy it was not difficult to construct a portable generating dev,ice. Manifestly such a source of power is not under all circumstances available, and when not available the machine is useless. Johnson brought into being a machine that successfully functions *639irrespective of this source of power, a machine capable of instant use wherever a limited number of men may be found to turn the cranks. This we think was new and novel. It d,id succeed. It is now in use, and admittedly is the only machine of its character capable of being used as it was designed for use, both in the field and on board ship.

Where the field is open for a long period of time, after the first attempts to supply a needed invention, such as the one in suit, have met with no substantial success, it is according to familiar patent authorities some evidence of invention and, to say the least, persuasive testimony that the final accomplishment of the desired purpose involves more than mere mechanical skill. Especially is this so when other experts in the art are striving during this interval to do the thing that is finally done. Judge Learned Hand, in delivering the opinion of the court in the recent case of *Westing - house Electric & Mfg. Co.*v. *Independent Wireless Telegraph Co*., 300 Fed. 748, 753, used these words:

> “ It is not important whether anyone before Armstrong had fed back oscillatory currents from a telephone circuit to a circuit tuned to the oscillations received by an antenna, and had so reinforced them. That might be admitted. No one had ever used that discovery to amplify the grid currents of De Forest’s audion, and Armstrong’s patent is confined to that. It took seven years to make the step, years in which the best electrical minds were at work upon wireless telephone. It is idle, at least, when the question arises in this way, to argue that such an adaptation was within the compass of the ordinary routine wireless electrician. Unless the delay can be explained, it is of itself good enough proof to lay any doubts as to the quality of the invention. I might therefore leave these references without further comment, merely on the chronology of the art.”

> Section 4920, R. S., Title XL, provides as follows:

> “ In any action for infringement the defendant iñay plead the general issue and, having given notice in writing to the plaintiff or his attorney thirty days before, may prove on trial any one or more of the following special matters: * * * Fifth, that it had been in public use or on sale in this country for more than two years before his application for patent, or had been abandoned to the public.”

*640The plaintiff, as the findings show, did sell to the Navy-Department five of the first type of machines for $400 each and received payment in full therefor. This sale antedated the patent in suit by more than two years. The record is emphatic that no profit accrued to the plaintiff from the sale. The defendant very properly raises the issue that the transaction described absolutely precludes a recovery under section 4920, inasmuch as the sets so sold differ only from the patent alleged to have been infringed “ in the production of the direct current to excite the field of the alternating-current generator.” Claim 2 of the patent in issue we think is anticipated by reference to the sets so sold. This claim, however, is not involved in this litigation. While we feel certain of a distinct departure from the sets sold in the respect insisted upon by the plaintiff in the patent at issue, yet, notwithstanding this fact, we are of the opinion that under the adjudicated cases section 4920 has no application in any event. The courts have repeatedly held that experimental use is not public use, and where an inventor makes a single sale for the sole purpose of experimentation he does not come within the meaning and intent of the statute. The line of demarkation is quite distinct, the difficulty lying in the ascertainment of the fact. The statute uses the significant words “in public use or on sale in this country for more than two years before his application.” Judicial precedent establishes beyond disputation that the designed purpose of the law was to preclude an inventor from the advantages of a patent monopoly where for the stated period of time he had abandoned the right to the public to use the invention or sought to profit from his enterprise in the usual and customary commercial way. Obviously the public was to be protected from the consequences of the patent law where an inventor for so long a time, indicated no intention of applying for a patent, or apparently had no idea that his invention was patentable, in other words, abandonment of the patent. If, however, a single transfer of the invention takes place under circumstances which clearly demonstrate that the transaction was consummated solely with a view of perfecting a device, one necessarily experimental, and the device is subsequently modified, changed, and perfected, in *641accord with the use for which it was transferred, then the so-called sale is not one coming within the law, but is experimental in character. Walker on Patents, 1923 edition, sections 93 and 94, pages 111, 112, 113, and 114, traces the origin of statutory law on the subject of abandonment in section 94, the author summarizing the law as follows:

> “ What is *‘*public use,’ within the meaning of the statute ? This question has now received light from a sufficient number of decisions, affirming or negativing the fact of public use in particular cases, to make it possible to deduce a nearly complete answer from judicial authorities.

> “ If the inventor allows hi/s invention to be used by other persons generally, either with or without compensation, then it will be in public use within the meaning of the statute. And the use is public, which follows a transfer of the thing used from its inventor to the user, without reserving any control over it and without expecting to make any change in it, or without any restriction.

> “ If the inventor uses his invention for profit and not by way of experiment, that is a public use, unless actual use resulting in profit is necessary to show the inventor how to perfect his invention and unless he does perfect it in accordance with the teachings of such use; but experimental use becomes public use when it extends further, either in time or in number of instances, than i,s reasonably required to test the invention. Nor will the fact that the inventor is but an employee in the place where he uses his invention, or the fact that the profit goes primarily to his employer, oust the operation of this rule.

> “ To constitute public use it is n,ot necessary that more than one specimen of the thing invented should have been publicly used, nor that more than one person .should have known of that use. Nor is it necessary to public use that the article used could have been seen by the public eye, if the ordinary use of such articles is veiled from view.”

Testing the single sale made by the plaintiff by the essential elements /stated in the above quotation, it is seemingly clear that the plaintiff’s case is not within the prohibition. First, the plaintiff did not realize a profit from the‘sale; second, the transfer was necessary to show the inventor how to perfect his invention; third, the inventor did not have available to himself the means to make the required test; fourth, the inventor did modify and perfect the machine in *642accord with suggestions arising from the te(st; fifth, no other sales were made of the machine and no attempt made to. place it upon the general market; sixth, it required a three years’ test before the machine met the complete expectations: of the inventor and the Navy.

The plaintiff cites copious excerpts from a multitude of cases, too many and too familiar to warrant citation, sustaining the principles to which we have just alluded. We think we may rest the issue upon what was said and has been repeatedly affirmed by the Supreme Court in the leading-case of *Root*v. *Third Avenue R. R.*Co., 146 U. S. 210.

*Resign Patent No. 4-8638*

The defendant challenges the validity of this patent. The patent was granted in virtue of section 4929 R. S., Title LX. Under the statute “ any new original and ornamental design for an article of manufacture,” etc., is patentable. The case of *Dietz Co.*v. *Burr & Starkweather Co.,*243 Fed. 592-594,. cited in defendant’s brief, construes the above statute, and in our view of the issue determines the question. Judge Hough,, in disposing of a similar contention, said the following:

“ To entitle an inventor to the benefit of a design patent, there must be originality, the inventive faculty must be exercised, mere mechanical skill is not enough. *Cary Co.*v. *Neal,*98 Fed. 617. *Steffens*v. *Steiner,*232 Fed. 862. The test for invention is the same for design as for mechanical patents. *Strause*v. *Grane Co.,*235 Fed. 131. All design patents appeal to the eye; they must present something pleasing and attractive *(Mygatt*v. *Schauffer Co.,*191 Fed. 836) and relate to appearance and to matters of ornament. The-utility of the patent depends on the effect upon the eye, not, to any new function; and such appeal is to the aesthetic emotion. *Rowe*v. *Blodgett Co.,*112 Fed. 61. The object of the statute is to encourage the origination of objects ‘ which give pleasure to the sense of sight.’ *Mygatt*v. *Schafer,*218 Fed.. 831. ,* * * Applying these rules to the matter in hand,, we are of opinion that McArthur’s lantern, or any lantern looking like that of the design, does not appeal to the aesthetic sense, and represents nothing more than a convenient shape for an article always purchased and used for what, it will do — not for its looks.”

*643The court had before it a physical exhibit of the design relied upon. Sitting as a jury in this respect, it would be difficult to return a finding that the casing presented any usual ornamental features “ appealing to the aesthetic emotion.” While we do not overlook the force and effect of the passing to patent of such a design by the Patent Office, we do believe from the evidence in the case that there is nothing of ornamentation or unusual characteristics of construction in the make-up of the casing which in any manner would arrest the attention of a prospective user as an article of beauty. As the defendant aptly suggests, “ the purchase by the United States of a generator was undoubtedly because of ‘ what it will do — not for its looks.’ ”

The defendant does not seriously contest the infringement of the claims involved, and we think that there is ample proof to sustain the judgment of the court that the plaintiff is entitled to recover.

The case is to be remanded for proof as to damages. The record is incomplete in this respect. Therefore it is ordered that the case be remanded and referred to Mr. Hayner Gordon, Special Commissioner of the Court, to take testimony upon this point and report the same to the court.

Moss, *Judge;*Geai-iam, *Judge;*and Campbell, *Chief*Justice, concur.