A PERPETUAL LOO, OR INSTRUMENT FOR MEASURING A VESSEL'S WAY THROUGH THE WATER, AND FOR ASCERTAINING THE RATE OF SAILING FOR ANY INSTANT OF TIME
Year: 1792

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
HALL GOWER, of Edmonton, in the County of Middlesex, Mariner, in the
Service of the Honorable the East India Company, send greeting.
me,
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent under the Great Seal of Great Britain, bearing date the
Fifth day of July, in the thirty-second year of His reign, give and grant unto
the said Richard Hall Gower, His especial licence that I, the said Richard
Hall Gower, during the term of years therein expressed, should and lawfully
might make, use, exercise, and vend, within England, Wales, and Town
of Berwick-upon-Tweed, my Invention of "A PERPETUAL LOO, OR INSTRUMENT
FOR MEASURING A VESSEL'S WAY THROUGH THE WATER, AND FOR ASCERTAINING
THE RATE OF SAILING FOR ANY INSTANT OF TIME;" in which said Letters
Patent there is contained a proviso, obliging me, the said Richard Hall Gower,
under my
hand and seal to cause a particular description of the nature of my
said Invention, and how the same is to be performed, to be inrolled in His
Majesty's High Court of Chancery within one calendar month after the date
of the said recited Letters Patent, as in and by the same, relation being there-
unto had) may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Richard Hall Gower, do hereby declare that my said Invention of a perpetual
log, or instrument for measuring a vessel's way through the water, and for

page_text: ascertaining the rate of sailing for any instant of time, is described in the plan
thereof hereunto annexed.
In witness whereof, I, the said Richard Hall Gower, have hereunto set
my hand and scal, this Twentieth day of July, in the year of our Lord
One thousand seven hundred and ninety-two.
W. GRAVES.
MCDARD HALL
WEK (L.B.)
AND BE IT REMEMBERED, that on the same Twentieth day of July, in
the year above mentioned, the aforesaid Richard Hall Gower camo before our
Lord the King in His Chancery and acknowledged the Specification aforesaid,
and all and every thing therein contained, in form above written. And also
the Specification aforesaid was stamped according to the tenor of the Statuto in
that case mado and provided.
Inrolled the Twants third day of July in the vane above writion

page_text: surface of the Water B a cylinder made of wood eighteen inches long and eight and three quarters Diameter inside; This bylinder is
ficed about a foot beneath the Float, by means of an Ion pame (The Cylinder in this representation is supposed hansparent, for the purpose,
of shewing the internal parts of the Instument Ca spiral consisting of the copper leaves pind on an Axis, each going through a
semicercle in its length and are extended out to the inside of the Cylinder. The length of this spiral is such as will cause it to
hun 2550 times in passing a geometical mile through water D. The Axis of the Spiral made of bravo, E, a warm upon
the Axis of the Spiral which plays in the two wheels FF "Two brass concenhic wheels of 50 and 51 teeth these wheels register the
huns made by the Spiral in a mile and are more fully described in Fig 3.4.5 and 6. G. G. Two brass bars which cross the
ends of the Cylinder and support the sperail. II. A brass pame which carries the register wheels F. so conhived, that the While
may
be taken out of the worm for the purpose of more readily placing them at Fero
7.2. Represents a side crew of the Spiral and Wheels out of the Cylinder
7.3. Represents in full vize, the brass pame II the wheels F and the worm I as they appear to a person standing behind the Instument
and looking through the Cylinder
4. Represents in pill size the face of the Register Wheels E I is the nonius -
K. The face of a small wheel which shews she mites - divided into 50 park, each part representing a mile I a pin to hun the wheel K
to Zero..
Figures 5 and 6 represent in full size the insides of the Register Wheels F and small wheel II.
i95. is the what F of 51 beth M. the inside of the wheel K of 50 Teeth:
N. a spring which binds against the Wheel K. and prevents it fan shifting its position while feed hom the tooth Qf Fig 6. Pa wove in which the tooth Q. Fig:
6 huns.
Fig: 6. is the wheel F' of 50 Teeth, divided into an hundred parts, each division representing the hundredth part of a mile, Q a tooth which takes
in the teeth of the small wheel N each time the wheel of 50 goes cound the wheel of 51, and pub it forward one divisions.
The method of using this Log.
The Register being set to Zero, let the Log be tracked along in the smoothest water to becward of the Ship, and let it be taken up at the end of
each four hours or certainly before the Register should be out but it must be taken up at the alteration of the course to know the distance sun upon the
last-course. The Distance given by the Log is to be placed down on the log board in miles and tenths or hundredths as may be thought fit.
This Inshument will be found useful in marind surveying for measuring a base line at a distance from the show where the headland can be seen.
NB. The description of the Glasses made use of when the Log is applied to shew the rate of sailing - vrst. They admit of being opened
at each end for the purpose of cleaning and taking out the particles at pleasure. The particles are perfectly globular, which prevents,
their adhering to each other, and to the side of the glass the fault in the present-Glasses made use of with the common
Log.
Drawn on Sture by Malby &