DIAGONAL 0 
The whole number. of fides race ge in. the 1-arcs, of 
which the flower confifts, will be’ foun d by add ing: ‘the num- 
bers in the gth column; containing the -Bolygonic’ ‘fides in 
each arc, to amount to 550. 1s, therefore, is: the num- 
ber of equal parts into which each wheel is to ivide 
previous to fie cutting. Ifthe machine will contain wheels 
of fufficient diameters, all this will be moft eafily effected by 
two wheels ; ; but when circumftances do not admit’ of this, 
two or more wheels may be ufed for each of the motions ; 
each of thefe wheels — a certain portion of the figure. 
by its revolution. In this cafe, the machinery communicat- 
ing the motion from the ret to the body which is to be 
acted upon, muft be fo conttructed, as to be {peedily and 
eafily moved from one wheel, and placed in conta with 
the others fucceffively, ‘This may be efie&ted by a dextrous 
aa in a great variety of ways, and the fuperiority 
of an e plan over others, mult depend fo much upon 
pe cla Seances, arifing b:th from ¥ com 
ftruétion of the machine, and from the fpecial purpofe for 
which it is defigned, that it would be equally d: oie cult and 
fruitlefs here, to fpecify precife modes of doing thi 
In the 4th, Sth, gth, roth, rith, aad ons ares laid 
down in the preceding calculation, no part of the arc croffes 
a horizontal line drawn through the centre, the whole being 
or below. As the table, No. 3, is calculated 
i i r to meafure 
and, of courfe 8 the table the firft angle of t 
are. hen an arc approaches towards the horizontal line, 
5 
the fucceeding ang'es mul taken fr om right to left, and 
when it eee from it, from left to right. 
hen arc does not crofs the horizontal five. the com- 
plementary angles w will be found in the r2th column. 
chinery contrucied for ‘the purpofe of tambour- 
ing, upon ee principles, the figures were mot frequently 
{mall, and the rows placed diagonally, fo as to form a kind of 
— _ A fpecimen of this application of the wheels will 
in fig. 22. In this fizure, eight flowers, exactly 
Brailee . suet other, are reprefen nted ; excepting only, sie 
the two flowersin the fecond, or m'ddle row, are inclined in 
a contrary direction to thofe in the firk and third rows ; that 
is to fay, that where the one row points towards the right 
hand, the next points towards the left; and the fame is the 
cafe in every alternate row, however numerous they may be. 
It is unneceffary to eater much into detail about the means of 
effeGting. this, for the whole difference is comprehended in 
the horizontal motion, and the ute both flowers is 
according to the explanation already giv 
placing. every row between that next to i is ; effetted alfo by 
the horizontal wheel. ne row is — ed in the circum- 
ference of the femi-diameter of the wheel, : peek eal circum- 
ference of the other femi-diameter is redu ced as nigher 
to the centre, as the — nce of one of the aa lines in ‘the 
rd is a the next li 
er pian was feactne es ufed. The whee Is were 
cut each of the fame comparative diameters, and the 
centering or bofomi of the alternate rows was produced, 
by g two intermediate fri€tion-wheels Rees the 
a and f = acte i sa as foun 
Ww 
h were alter- 
the eels 
pately ufed, each pane employed hon its eipei row, 
Pe en ee 
. But, as time was loft 
cngagi a ae Geiger g the het at every 
5 
; 8 
CD: 
° 
cB 
tm 
bes 3 
oe, 
: Bes 
Fess 
“te 
“1 
tes we) 
fas 
i 
o 
a 
4, ae! 
ea 
"ke; 
lou 
ee. 
fa) 
eed fet 0 rather 
Smee applying the threads necef- 
fary to the, operation. was neceffary, therefore, to 
fhift, it was found ¢ afler’to fhift the vertical ane ane 
the cloth, than the frames both ‘be fore and be hind , hen 
nthe middle - ‘figure of the saline line, the oe 
are aa to the centres, asin jig. 21. They coniit of 
our arcs, or feginents of circles, as follow: 
Are 1to2 Centre b Diameter 
rte 
Are 95° 
- (225 
50 
705 go 
The dotted lines jae ‘pon. the | an ‘e, ferve both to 
afcertain the refpeGtive aiftances of the Howers, to fhew the 
i fubtending the ares, and alfo the complementary an- 
» - @ 7 
ate 
5to6 + = d oe 
gee ot t9 
ul yes} 
“wana 
“The angle had {ubtends the arc 1to 4, which contains 
- The angle 241, the are 1 to 2 of 95° 
The angle 5 ¢6, the are 5—6 of 56 
The angle ad5, the arc 7—5 of go 
Two {mall arcs remain to join the points of the leaves. 
They ae betaken as femicircles, the diaméters of which 
areeach 48. The fir upon the upper leaf commences at 
45°; the fecond on the lower leaf at o°. Each, of courfe, 
is 180°, or two quadrants. Every other part neceflary will 
be found by meafurement, or by referenee to the tables, 
asin the former cafe, and thus any figure may be produced. 
The 
firft requiresonly two wheels; the fecond three wheels, for 
the purpofe of making the faint and bold lines. In thefe, 
the tracer, refembling that conduéted 
hand, may either be fuppofed to move, and the tablet to be 
ftationary and horizontal, as in sence writing, cv the ta- 
ble Leal desea and the pen horizon 
ae within the a oe of a ienetea to enter 
ae: examination of the sig aa of the various let- 
aor alphabet, as fed in that kind of hand-writing 
moft approved in Britain. oe pcos more properly to 
the analyfis of the art o anfhip, than to an eflay or 
‘treatife on the prodution ae diverfified motion by the agen- 
cy of machinery. In gen 
= 
c 
without at all entering into a 
proper forms; for, fro’ ae: 
and the defcriptions aleeay given, it will be evident, that 
; ight 
x 
The letter O is reprefented by 
an ‘elliptey the ee ae of which is an inch, or in 
\ the 
—- a. ba eS rae oe : - cee eee 
