FUSEE. 
the fufee, 
evident, vee ae that if one hand of 
the winch, I, while the other is ee gently (aga the 
handle, U, of the cutting-tool, a groove will be made 
the furface of the fufee of fome ane number pe re- 
ae which fhall depend on the quantity of the bar’s 
inclination, that. regulates the motion of the prifm; and as 
this saree is adjuftable, a 
ma a be affine adjuftment, 
e to be cut. 
inne, the regulation of the prefire by hand i ml 
e very nice, to make the tock cut the groove of equal de 
in every part of the furcellve revolutions pha the cae 
is continually vary ing it its any 
inaccuracy that is liable to arife this peace — 
i'vench have applied a piece of meal ane into the prope 
i cendhe curve, asa gui uide, or gauge, for the run of ce 
cutting tool, fuch as is reprefented by ae ig. 35 which we will 
deferibe as adapted to our ee ae though it was ap- 
es 
- 
plied, accordings to F. Berthou . Lelievre to an en- 
wine, contrived by him, of a entrain nearly fimilar to 
the o e e ie iding frame 
moved horizontally, whereas our’ ye 
Ta the figure laft named, “A B is a i Fame carrying 
ee os tool U, and its fupporter T, adaptcd to the 
prifm Q, im fig. 13 but at C, where the c ursog ae is 
Pomeeed with A B, is a piece of metal formed into an hy- 
fie cur ve, as feen detached at D, near the faid figure ; 
this cu or gauge, is formed by the we laid bein in, 
our ee article Fusrr, and i d by a clamping 
piece, E, with a thumb-ferew at the mone | en, as. 
to depth, while the ferews at the ends of A B adjuft the la- 
teral pofition, for the kngth of the fufee, by means of the 
oblong holes that allow the whcle frame of this figure to 
flide to the right and left, as occafion may require, before 
it is finally fixed for aétion. . In this fituation of the appa- 
ratus, a ae is pecans fatt into ftem of cutting tool 
near C, © be in contact w the curve; 
ic oie 18, that _ ihe 
r prifm in e-. 
Tey 
ances in ‘a lateral ‘dined ction, ne the ide of the. ful, and. 
the bottom of the fpira] groove thus cu a given. 
ged 
depth, depending not on nthe fhape of. nae fufee ‘fel, but. es 
1 
the cuit ing poin 
of, been “uled in “Ea land, ee its ingenuity and 
aa lity,.a may be, that, as we have ob- 
before, ae seta {pring, ufed as a main-fpring, 
requires its. own appropriate curve, and i it would be endlefs 
to havé a curved. piece made ,for ever e that is. 
to be cut by the engine: befides, a fpring i is rarely Se 
uniform in its variation .of force with the variation of tenfion, . 
throughout its whole, time.of uawin ; fo that, after all 
tentatiy e oo of, ‘the de th. oF certain,, ae to 
sferiain pee dim 
and grooved, tH oa a b 
cia. er, Coole, nd-may be rae at 10 L, of 
Horol cy,3 and co any, perticular 2 part of the fusee. requires . 
to be ren inithed, or to its,groove deepened, the fulee 
is put either, into, a ‘cousnon eae foapne, or into the ¥F USEE 
) 
- near the laft named wheel- 
af 
the mean time, being made - patanle $ ide is frames heen a (fg. 3. of Plate XXXVIT.) and 
the 
fuffer ed to 
part of the fufee that bas been altcre 
in the fpiral groove of a fufee may be 
force of the {pring ie which it 1s to be 
of the frfee-tool, ane never < _ omitted when a new 
main-fpring is frft ufed in aay watch or clock, however olds 
for as foon might we ex pect that the expanfion of mercury, 
in a new tube, would correfpond to an old feale silage 4 
made, as that a new main-lpring {i {hall have its extreme and 
intermediate forces = tly compenfated by an old fafee with- 
out new adjuitment 
Spear ating byt - union ofa, Loree, a double lever 
and a pair of w gine which we now come, 
to deicribe unies the 
the fcrews, and the double lever, to modify the refpective 
motions of the fulee aid of the cutting tool, in the tollow- 
j iC in fig. 4. Of the Init plate, is a plate of 
_ brafs fixed, or otherwile ia on a table, during the act 
of ufing the engine now before 
pair of t puppets, dea eee eee to the plate A B, 
united refpectively by the ed ew lying on ne fai 
a : i : ame one fs 5, teen there detached, 
Tac en the two oem to 
which it will fi Hide. par veal befure it is fixed by) its thumb- 
vw beneath; this finall frame receives the fufee between 
its cylin holding pieces I. and F, and the- piece It - 
over ufed as a ftud for a loofe wheel to revolve roun 
NS 
o. 
a : 
communicates motion wh the wheel revolves; this 
not hes aoe faft on the tap pped arbors, 
ts in a hole made in the pu pet-Cy 
near the winch, and is fupported at the other end by a cylin- 
rical piece with a conical point, e ugha the-hole of the 
board therefore the winch is a. 
dean will oa pe though no 
all in the fame cave nor yet e fame tine, unlefs 
the two wheels have like dine tone and ae of teeth. 
The perfo yee oS piece if tapped to 
receive ayes ferew of the arbor, : pr -_ ae from turmang, - 
i uid, as the ioe. by a projecting piece below ity: 
rat ere a fixed ilrong wire. HK <, which flides, or is 
, - Fel to fide, in two cock s ferewed to the aaa 
and C, as feen in the figure ; therefore, when the arbor co 
taining the male {crew re an ae s, by means of its w inch, a 
the eed a Ove female ferew, is drawn , 
winch peel i 
Pie 
the w, which aa ore. ought not to 
cae ner the tapeeeion: i this refpeét 3 but the 
G would be at liberty;to travet along the wie mais of 
the arbor, if fee were no {tops at the: limited diftances: to 
obviate this, the wheel on the tapped arbor a pin alfo 
projecting from its s plane, and the two fliding pieces L and - 
M will clamp a y given points 0 of the wire jut deed ; 
the wire is cran! ked fo as to per- ¢ 
n its prefent - pofition, 
ape will 
nee with ‘the clamp L, 
before it, till the angular part of the crank falis in the w vay 
of the wheel’s spin, when all further motion is arrefted by the . 
locking ct the whee ls a oN motion will alfa lock the 
“wheel | 
