AN IMPROVED MACHINE OR INSTRU- MENT FOR CALCULATING AND ASCERTAINING THE LONGITUDE AT SEA
Year: 1817

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANTONIO
JOAQUIM FREIRE MARRECO, 'of Broad Street Buildings, in the City of London,
Merchant, send greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-ninth day
of April, in the fifty-seventh year of His reign, give and grant unto me, the
said Antonio Joaquin Freire Marreco, my exors, adñiors, and assigns; His
especial licence, full power, sole privilege and authority, that I, the said Antonio
Joaquim Freire Marreco, my exors, adñiors, and assigns, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, my Invention of "AN IMPROVED MACHINE OR INSTRU-
MENT FOR CALCULATING AND ASCERTAINING THE LONGITUDE AT SEA ;" in which
said Letters Patent there is contained a proviso obliging me, the said Antonio
Joaquim Friere Marreco, under my hand and seal, to cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, to be inrolled in His Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said

page_text: recited Letters Patent, as in and by the same, relation being thereunto had)
may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Antonio Joaquim Freire Marreco, do hereby declare that the nature of my
said Invention, and the manner in which the same is to be performed, are
particularly described and ascertained in manner following, reference being at
the same time had to the Drawings hereunto annexed, marked respectively
with the letters A and B (that is to say):-
My said machine or instrument, which I denominate a Cosmometer, because
applied to the measurement of the world, is a cylindrical box or case made of
brass or any other fit metal, seven or eight inches (or more or less) in diameter,
and one inch (or more or less) in height, containing some simple mechanism,
hereafter described, and presenting on its upper or horizontal face certain circles.
more particularly noticed hereafter, and which said circles constitute a most
essential part of my said instrument, as they represent therein great circles of
the heaven and of the earth, for the adjusting of the relative position and
motion of which, there are indexes, or minutes and seconds bands, over the
said horizontal face.
Figure 1 represents a vertical section through the centre of the said instru-
ment; Figure 2 represents the horizontal face; and Figures 3 and 4 represent
parts of the internal mechanism, which could not be so distinctly exhibited in
the said section (Figure 1). The box or case a, a, (Fig. 1,) is divided into
an upper and a lower compartment by the plate b, b, parallel with the face
and bottom of the instrument, excepting the part about the centre where it
descends in the form of a kind of cup, as shown in the Drawing. From the
centre of this cup a vertical hollow axle c, c, rises to the height of the face of
the instrument. The cylindrical part of the said case a, a, and the said
plate b, b, which divides it into two compartments, and also the said cupped
part and the said vertical hollow axle c, c, are all in one piece, formed at one.
casting, and well and truly turned in a lathe, in order that the said hollow
axle may be and remain true and correct in relation to the other parts of the
said instrument. (In the Drawing the said cylindrical part a, a, the said
plate b, b, and the said cup, and also the said hollow axle, are, for the sake of
more easy discrimination, tinted yellow.) A wheel of 360 teeth d, e, c, d,
(tinted brown in the Drawing,) has its axle e, e, perforated and fitted to the
said vertical axle c, c, on which it turns very exactly and truly. The part d, d,
of this wheel rises to the top of the cylindrical box, and presents a circle which
forms part of the face of the instrument (see the middle figured circle tinted
brown in Figure 2). This circlo represents in the said instrument a great

page_text: circle of the terrestrial sphere, and is divided into 360 degrees, marked in
(Figure 2) by numerical figures in the following order :-30, 60, 90, 120,
150, 180, 210, 240, 270, 300, 330, 360. This circle turns very truly
between the outer and inner figured circles (Figure 2) yet to be described.
The circular recess 7, r, (Figure 1,) within the circle d, d, receives a dial
plate n, n, (tinted green in the Drawing,) of about five inches in diameter (or
more or less according to the size of the instrument). This dial is twice
divided into 60 for the purpose of shewing minutes and seconds of a degree.
(See the inner circle of Figure 2 marked with the numerical figures 5, 10, 15,
20, 25, 30, 35, 40, 45, 50, 55, 60.) This dial is made fast to the upper part
of the hollow axle c, c, (Figure 1,) by two or more screws i, i, and con-
sequently does not revolve. The circular recess 9, 9, (Figure 1,) between the
said circle d, d, and the cylindrical side of the box a, a, receives another
circle m, m, (tinted red in the Drawing,) which is inserted in and made fast to
the cylinder a, a, by three or more screws 8, 8. This circle m, m, represents
in my said instrument a great circle of the celestial sphere, and is divided into
twelve equal parts, marked with the names and characters of the twelve signs,
beginning with Aries, and ending with Pisces. (See the outer circle tinted
red in Figure 2.) Each sign is divided into thirty degrees, and the whole
circle is marked with numerical figures in the same order as those on the
circle of he wheel of 360 teeth, d, d, already described. This circle, in like
manner as the inner dial or circle n, n, remains stationary, being, as already
noticed, made fast to the box or case. The vertical axle c, c, receives another
hollow axle o, o, (tinted red in the Drawing,) to which the horizontal snail
plate u, u, (Figure 1,) is attached, the said axle o, o, and the said snail
plate u; u, being in fact one piece of metal, cast and turned and worked into
form. For the shape of the said snail plate see u, u, Figure 3. To the top of
the said axle o, o, the minute hand v, v, is made fast by two screws (shewn in
their place in Figure 1). The said snail acts on a swing lever A, B, C,
(Figure 3,) turning on its own pivot D. Every time that the minute hand is
made to perform one revolution, the said swing lover, in receding from the
centre 9 (while passing from the lessess diameter C to the greater diameter E)
moves the dented section of the alternating wheel F (tinted red) by means of
the short dented rack (or portion of a wheel of which D is the centre) formed
on the end B of the bar A, B, of the swing lever A, B, C. The axis of the
said wheel F carries (attached on it) a pinion of eight leaves, which works in
the said wheel of 360 teeth (d, d, Figure 1), and every time that the wheel F
is acted upon by the said swing lever (that is, by every revolution of the
minutes hand) the said pinion propels one tooth of the said wheel of 360 teeth.

page_text: The wheel F is a cylindrical box containing a ratchet and click, which enables
it to act, turning its axis on every recession of the said swing lever from the
centro 9 (Figure 3), and thus moving the pinion, which it leaves undisturbed
when it receives its alternate motion froin the said swing lover on the return
of the said swing lever towards the centre by the pressure of the constantly-
acting spring G, B, (Figure 3,) which always keeps the swing lever in contact
(at c) with the edge surface of the snail plate; that is to say, by each revolution
of the minutes hand the swing lever moves the alternating wheel. F, and thus,
giving motion to the said pinion, propelling the wheel d, d,.(Figure 1,) one tooth;
but on the return of the swing lever the wheel F slips back. (the ratchet and click
having no action during its return), leaving the axis and pinion stationary, 'and
which are kept steady in their place by means of a kind of small star wheel
(k, Figure 4) of eight radii, which is made fast on the axis of the said pinion,
and which is pressed upon by the curved face of the head 1 (Figure 4) of the
check spring H 1 (Figure 3 and Figure 4), the snid curved face resting its
most prominent part between two of the said radii of the said star wheel K.
with sufficient force (by means of the action of the spring) to keep it from
moving till, by the revolution of the minutes hand, the swing lever (by means
of the mechanism that has been described) propels another tooth of the
wheel d, d, (Figure 1,) when the advancing. radius or tooth of the star wheel
is made to slide over the curved faco of the said spring head H, the spring
yielding to allow this, after which it again acts as a check to keep. the pinion
stationary till moved again by another revolution of the minutes hand. (The
star wheel on the axle of the alternating wheel F is shewn, with its check
spring, in a separate Figure (Figure 4).) A plate of metal,, (Figure 1,)
(tinted green in the Drawing,) forms the bottom of the case, and is kept in its
place by four or inore screws. A central axis w, w, (Figure 1,) passes
through the bottom, through the hollow axle o, o, and up' through the face of
the instrument. This axis, which is squared at its top, receives on its square
the seconds hand a, e, which is secured in its place by a small horizontal pin
which passes through a little brass collar (tinted yellow), over the said seconds
hand, into the central axis, against the lower end of which a thin, elastic
button y, w. (Figure 1,) turning on a piu y. presses to keep it in its place.
The axis of the pinion comes through the face of the instrument near the outer
edge of the circle which represents the great circle of the celestial sphère,' and
is surmounted by a knob or milled head L (Figure 1 and 2) for adjusting the
circles for operation according to the place of the cartli adopted for the first
meridian, and an arrow is engraved on the terrestrial circle, pointing to the
celestial, for determining the first meridian. Both the minutes and seconds

page_text: hands are furnished with vertical descending points, which are received into
the dotted divisions on the central dial plate wherever they are wished to be
made to rest.
In witness whereof, I, the said Antonio Joaquim Freire Marreco, have
hereunto set my hand and seal, this Eleventh day of September, in
the year of our Lord One thousand eight hundred and seventeen.
A. J. FREIRE MARRECO. (L.s.)
AND BE IT REMEMBERED, that on the Eleventh day of September, in
the year of our Lord 1817, the aforesaid Antonio Joaquim Freire Marreco
came before our said Lord the King in His Chancery, and acknowledged the
Specification aforesaid, and all and every thing therein contained and specified,
in form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute made for that purpose.
Inrolled the Eleventh day of September, in the year of our Lord One
thousand eight hundred and seventeen.