IM- PROVEMENTS IN APPARATUS FOR TAKING LEVELS AND MEASURING ANGLES
Year: 1859

page_text: LETTERS PATENT to Patrick Adie, of the Strand, in the County of
Middlesex, Mathematical Instrument Maker, for the Invention of "IM-
PROVEMENTS IN APPARATUS FOR TAKING LEVELS AND MEASURING ANGLES."
Sealed the 1st April 1859, aud deted the 4th February 1859.
PROVISIONAL SPECIFICATION left by the said Patrick Adie at the Office
of the Commissioners of Patents, with his Petition, on the 4th February
1859.
I, PATRICK ADIE, of the Strand, in the County of Middlesex, Mathematical
Instrument Maker, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN APPARATUS FOR TAKING LEVELS AND MEASURING ANGLES," to
be as follows:-
The improvements relate to arranging the instrument known as the ordinary
levelling telescope with parts in connection therewith, that the same may also
be used as a theodolite. For this purpose the level telescope is formed to be
supported on either of two axes at right angles one to the other, the one being
in the line of the colination of the telescope, and the other at right angles to
that or similar to the transit axis in a transit instrument. The bearings of the
first axis work in y's, which I prefer to be circular, or having more than a
simple tangential bearing; these y's being so screwed upon or formed with the
stage plate of the level as to get rid of the continual alteration in the adjust-
meutof the y's as in the old y level, and when the instrument is used as a level
دي

page_text: the colimation journals rest and are held in these y's by brass straps or screws
applied to either pair of journals. The second or cross axis, at right angles to
the line of colimation of the telescope, is designed to adapt the telescope to
the mensuration of angles, as in the transit theodolite. It is fixed at or near to
the middle of the telescope, so as by releasing the colimation axis and lifting
up the telescope, the journals of this axis are made to fall into a pair of y's
on piers, also firmly fixed on the stage plate of the level, these y's being of
sufficient elevation to allow the telescope the required meridianal motion for
the ordinary undulations of the earth's surface.
The horizontal or azimuthal angles are read on a divided limb with verniers
placed under the horizontal plate of the level, which limb works on the
outside of the boss or hollow centre, in the interior of which the centre which
turns the level plate, telescope, and verniers turns.
When vertical angles are required to be measured, I propose to do so by a
circle or arcs and verniers applied somewhat in the usual way. The lower
portions of the instrument are to be constructed also much in the usual
manner.
I fix and adjust the level tube by pushing and pulling screws working
against two planes at right angles to one another. These screws work in the
level ends in pieces, also fixed at right angles to one another; the one being
for elevation, the other for horizontal adjustment.
To obviate the difficulties arising in the use of the instrument on uneven
ground, I sometimes construct the tripod on which the instrument stands with
legs of unequal lengths.
Also I adapt a graduated spring measure with a plum bob attached to
measure the height of the line of colimation from the bench mark when used
as a level, or as a simple plummet when used as a theodolite, which, working
by a spring and stop, or such like means, gives great readiness of use, and is
of great convenience arising from its being packed in the tripod itself.
Also the improvements relate to the application of verniers to the compass
needle when used for measuring horizontal angles; the needle itself in this
arrangement being suspended by a fibre, the support of which is attached to
the stand or tripod of the instrument, and is thus stationary while the divided
arc or circle is moved round with the telescope.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Patrick Adie in the Great Seal Patent Office on the 4th
August 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PATRICK
ADIE, of the Strand, in the County of Middlesex, Mathematical Instrument
Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of February, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Patrick Adie, Her special licence that I, the said Patrick Adie,
my executors, administrators, and assigns, or such others as I, the said
Patrick Adie, my executors, administrators, and assigns, should at any timo
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
APPARATUS FOR TAKING LEVELS AND MEASURING ANGLES," upon the condition
(amongst others) that I, the said Patrick Adie, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of their hands
and scals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Scal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Patrick Adie, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
The improvements relate to arranging the instrument known as the ordinary
levelling telescope, with parts in connection therewith, that the same may also
be used as a theodolite. For this purpose the level telescope is formed to be
supported on either of two axes at right angles one to the other, the one being
in the line of the collimation of the telescope, and the other at right angles to
that or similar to the transit axis in a transit instrument. The bearings
of the first axis work in y's, which I prefer to be circular or having more than
a simple tangential bearing; these y's being so screwed upon or formed with
the stage plate of the level as to get rid of the continual alteration in the
adjustment of the y's as in the ol level, and when the instrument is used

page_text: as a level, the collimation journals rest and are held in these y's by brass
straps or screws applied to either pair of journals. The second or cross axis
at right angles to the line of collimation of the telescope is designed to adapt
the telescope to the mensuration of angles as in the transit theodolite. It is
fixed at or near to the middle of the telescope so as by releasing the collima-
tion axis and lifting up the telescope, the journals of this axis are made to fall
into a pair of y's on piers, also firmly fixed on the stage plate of the level,
these y's being of sufficient elevation to allow the telescope the required
meridianal motion for the ordinary undulations of the earth's surface.
The horizontal or azimuthal anglesare'read on a divided limb,with verniers
placed under the horizontal plate of the level, which limb works on the outside
of the boss or hollow centre, in the interior of which the centre which turns
the level plate telescope and verniers turns.
When vertical angles are required to be measured, I propose to do so by a
circle or arcs and verniers, applied somewhat in the usual way. The lower
portions of the instrument are to be constructed also much in the usual
manner.
1 fix and adjust the level tube by pushing and pulling screws, working
against two planes at right angles to one another. These screws work in the
level ends in pieces, also fixed at right angles to one another. The one being
for elevation, the other for horizontal adjustmont.
To obviate the difficulties arising in the use of the instrument on uneven
ground, I sometimes construct the tripod on which the instrument stands with
legs of unequal lengths.
Also I adapt a graduated spring measure, with a plumb bob attached, to
measure the height of the line of collimation from the bench mark, when
used as a level, or as a simple plummet when used as a theodolite, which
working by a spring and stop, or such like means, gives great readiness of use.
and is of great convenience, arising from its being packed in the tripod itself.
The improvements relate, secondly, to the application of verniers to the
needle when used for measuring horizontal angles. The needle itself
in this arrangement being suspended by a fibre, the support of which is
attached to the stand or tripod of the instrument, and is thus stationary, while
the divided arc or circle is moved round with the telescope.
compass
But that the nature of my Invention and the means I adopt in carrying
the same into effect may be better understood, I will proceed to describe
the Drawings annexed, in the various Figures of which the same letters are
used to indicate like parts wherever they occur.

page_text: Figure 1 shews a plan view of apparatus arranged according to the first part
of my Invention; Figure 2 is a side view of the same. In each of these views
the parts are drawn in black lines, as they would be when the instrument was
intended to be usedsimplyas an ordinary levelling telescope, whilst by Figure3,
and by red lines in Figure 1, the parts are shewn in position for the instrument
to be used as a theodolite; Figures 4, 5, 6, 7, 8, and 9 shew some of the parts
separately; is the telescope (shewn separately by Figures 4, 5, 6, and 7,)
which it will be seen is formed with two pairs of journals a', a¹, and a², a²,
forming axes of motion at right angles the one to the other, and by which it may
be differently supported according to the purpose to which for the time being
it is to be applied. The journals or axes a', a', are in the line of collimation
of the telescope, and when, as stated, the instrument is to be used as an
ordinary levelling instrument, those journals a', a', will be supported in the
y's b', b, which are screwed upon or may be formed with the stage plate b, in
place of being formed adjustable with a set screw to one or both of them as
is the usual practice, and by which they are liable soon to get out of order
and to fail of correctness.
These y's b', it will be seen, are formed to embrace closely the journals a¹, in
place of only supporting them at two or four points, and thesenecks or collima-
tion journals are held in these y's b₁, b, by the straps 62, 62, or in place of these
straps, screws may be employed if desired.
Upon the stage plate 6 are also formed the piers 63, with y's at their upper
parts adapted to receive the journals or axes a" of the telescope (as indicated
by Figure 3 and the red lines Figure 1), when the instrument is to be used as
a theodolite for measuring vertical angles. And it will readily be understood
that when desired to shift the telescope a from the one pair of bearings or y's
to the other, it will only be needful to release the straps by which the respective
axes have been held, in order to their being held in the other bearings or
pairs of y's, and the y's to the standards or piers are provided with straps 6³,
so that when the journals a² of the telescope are placed therein, they may be
held there securely as is well understood.
It will be seen that these piers & are raised sufficiently high above the stage
plate b to admit of the telescope being moved for ordinary undulations of the
earth's surface, but their height may be varied. c isthe horizontal limb which
is read or divided on the bevil edge c', placed under the horizontal plate or
stage ; 65, 65, are the verniers affixed on the opposite sides of the plate 67,
which overlaps to protoci, the divided limb c'. The limb c' is formed with a

page_text: collar c, which works on the outside of the boss or hollow centre d, forming
part of the parallel plate d', and it is within this boss or hollow centre d, that
the centre or axis 6 of the stage plate b, carrying the telescope and vornier
plate is supported and turns. The collar c is held stationary ou the parallel
plate d by the clamp and tangent screw d², d³, as required.
When, in using the instrument as a theodolite, it is desired to measure
vertical angles, I do so by applying thereto the part of the instrument shewn
separately by Figures 10 and 11, consisting of the divided circle e, verniers c¹,
and level e, with adjusting means, such as is well understood. ff, are
adjusting screws, adapted somewhat in the ordinary way for setting that part
of the instrument. g is the level tube, which is supported at its ends upon
the standards a³, ³, from the telescope a, by means of pushing screws g'g¹,
and pulling screws g², g², and it will be seen that the planes of the connecting
surfaces with the adjusting screws of the opposite areat right angles, one to
the other, by which I am enable to obtain a very simple and ready mede of
adjustment. By that, at one end of the level tube, I am enabled readily to
obtain adjustment for elevation, and the other, that in a horizontal direction.
The instrument will be applied to the ordinary tripod,as is well understood,
but to obviate the difficulties arising from the use of the instrument on unoven
ground, I sometimes construct the tripod with legs of unequal length.
In order to facilitate the measuring the height of the line of collimation of
the telescope from the bench mark, when the instrument is used as a "level,"
I affix to the under side, by preference, of the head of the tripod, a spring
measure with a weight at the end of the tape, to act as a plumb bob; and at
the same time, by being let down to the bench mark, and the height from the
tape to the collimation line being known to indicate the height of the line
referred to. When the instrument is being used as a theodolite,the tape may,
by its weighted end, act simply as a plumb bob. The tape I prefer to use for
the purpose is that which is wound up by a spring enclosed in the case, and
acting with a catch to stop the motion when required; and by its being attached
to the tripod, considerable simplicity and convenience will be obtained.
Figure 12 shews a sectional view, and Figure 13 a plan view of an instru-
ment for measuring horizontal angles,constructed according to the second part
of the improvements. The needleh, it will be seen, isformed with a vernier'at
each end thereof, and it is suspended by a fibre 2 from the upper part of the
internal tubei, which is supported from the nut i,affixed to the stem carried
by the tripod of the instrument; jis the divided circle carried by the framej,
which by its collar is supported so as to turn freely on the part.. jis a
glass cover to the frame j, to protect the needle; and to the centre of this

page_text: glass cover is affixed a tubej', enclosing the tube i. The frame 7 also carries
the standards, carrying the axis of the telescope k.
Having thus described the natureof my said Invention,andin what manner
I carry the same into effect, I would have it understood that I do not confine
myself to the precise details shewn and described, as these may be varied;
but what I do claim is,-
First, the adaptation and combination of means, whereby the instrument
known as the levelling telescope is adapted to be used also as a theodolite,
in manner substantially as explained.
Secondly, I claim the modeof arranging andcombining parts of apparatus
as described, in respect of Figures 12 and 13.
In witness whereof, I, the said Patrick Adie havo hereunto set my hand
and seal, this Fourth day of August, in the year of our Lord One
thousand eight hundred and fifty-nine.
Witness,
WILLIAM BROOKES,
73, Chancery Lane, London,
Patent Agent.
PATRICK ADIE. (L.S.)