DIAGONAL. 
ought to be ager a ee by the engineer to the 
effect which he in The » intended 
€ 
8, being the revolutions of a hand 
es 
tical motion was = circular, fo as to 
upon the body to be moved. If vertical, the fame was 
done with the laneonial whee 5 3 and when oblique, a devia- 
angle of obliqdity from a horizontal ftraight line. Thus 
the horizontal motion reprefented the bafe; the vertical 
motion the perpendicular; and the combined ae eae mo- 
tion the hypothenufe of a rig eos ea Ase 
of thefe mu 
by 18, it becam o 
ratio which the hypothenule, whofe meafure was 18, bore to 
the bafe and perpendicular ee ee meet from 
Minutes and fec were eckoned, 
ae unneefary, aad ce a degree, ae or below, 
was taken e table, caleulated by the common trigono- 
metrical vnalogies, making the hypothenufe radius was as 
ollows 
Table I. fhewing the length of the bafe and perpendicular 
of any right-angled triangle, the meafure of the pee 
being 18, and calculated for every degree, from 0° to go 
pp 
w 
Bafe. | Perp. Bafe. | Perp. 
0°] 18.0 | 0.0 | go°l] 23] 16.6 | 7.0 | 67 
I | 18.0 0.3 | 89 |] 24 } 16.5 7-3 | 66 
2 | 17.9 0.6 | 88 |} 25 | 16.3 7.6 | 65 
1 37 17.9 0.9 | 87 || 26} 16.2 769 | 64 
4 | 17-9 1.2 | 86 || 27 | 16.0 8.2 | 63 
ee ve). 1.5 | 85 |} 28} 15.9 8.4 | 62 
6 | 17.9 1.8 | 84 || 29 | 15.7 8.7 | 61 
71 179 2.2 | 83 || 30 | 15.6 | 9.0 | 60 
8} 17.8 2.5 | 82 || 3r ] 15.4 9-3 | 59 
9 | 17.8 2.8 | 81 || 32 | 15. 9-5 | 58 
oj 17.7 3.1 | 80 || 33 | 15.1 g-8 | 57 
TI | 17.7 3-4 1790 || 34 | 14-9 | 10.1 | 56 
12 {317.6 | 3.8 | 78 |! 35 1 14.7 | 10.3 | 55 
13 | 1765 4.1 | 77 || 36) 346 | 10.6 | 54 
14} 17-5 | 44 | 76 || 37 | 14-4 | 10.8 | 53 
15 | 17-4 4:7 175 |{ 38 | 14.2 | 1r-6r | 52 
16 | 17.3 5-0 | 74 || 39 | 14.0 | 11.3 | 51 
17 | 17.2 593 + 73: || 40 | 13.8 | 11.6 | 50 
18 | 17.1 56 | 72 11 41 113.6 | 11.8 | 49 
19 | 17.0 5-9 | 71 || 42 | 13-4 | 12.0 | 48 
20 | 16.9 6.2 | 7o || 43 | 13.2 | 12.3 | 47 
at {i168 | 6.5 | 69 || 44 | 13.0 | 12.5 | 46 
22 | 16.7 6.7 | 68 || 45 | 12.7 | 12.7 | 45 
Perp. | Bafe. Perp. | Bafe. 
means of the en 
5° are the ss 
logarithmic tables, 
Fig. 17, thews the angles of obliquity for every 10°. Th 
bafe line, or horizontal motion, there becomes the co-fine, 
aad the perp:ndiculir, or vertical motion, the fine of the 
% 
angles at the centre A of the quadrant BC. The trian- 
gies are reprefented by the radi, the bafe, and the perpendi- 
culars drawn from the divifions of the quadrant to the bafe, 
and numbered from I to 8. 
The general principle being thus reduced to the commoa 
application of right-angled trigonometry, it may now be 
he ind in Biitain, and of which repre- 
lease will be found in Plate VI. 
Dividing and Cuiting Engine. 
This engine, as formerly noticed, is, in fome ref] 
fimilar to Mr. Ramfden’s dividing engine. 
with this the properties o 
c 
pect, 
It alfy ane 
The enpine 
ma s en aye confined * de Ste = pape the 
rims of aes wheels as have been already noti and never 
was applied to the purpofes for which the common cutting 
engine is ufed. In Plate VI. fi. 18, 1 is a ground, or hori- 
zontal plan, of every part of the engine which can be feen, 
en viewed from 
citinly the parts under them, The 
18, appear very plainly in the profile elevation, fig. 19. 
The length of the engine is four feet, and its breadth Ge 
€ 
e cut, by any engine conftrudted for a fimilar purpofe. 
The diameters of the wheels cut by this oo 
inches at the moft remote point = we centres, 
tre 
s by the revolution of 
18 5 ; ‘and as 8 the cutters were 
ike the common engin e, this cu 
a circular cutter upon its own ax 
[crews and nuts. T’he upper oa of this \aming is repre« 
fented at ABC To this upper part are {crewed fou 
pieces of iron, ; » which ferve as fupporters and 
guides for the iron frame EE; fo that the fram 
of the fcrew, which, pafling through the iron frame at I, 
has its other end eee by another fixture to the wood 
work at K end of the large {crew is counterfunk to 
receive the te oe a oom {crew pafling through the fix- 
ture at K, which may be {crewed up, when neceflary, to keep 
the fhou a af the lange aes gee to the bufh, H, in which 
it revolves. When the fcrew is 
lef 
worked 
which only can be feen »in fg. 18, but which appears 
very aa in the profile aia: of the engine, fig. 19, 
and the perfpective view, he worm is fixed upon 
an iron axis, ftretching ae ne engine fupported at either 
end by bufhes: fcrewe - , and turned by the 
winch, or handle, N. xis ts another {maller 
Upo 
wheel, reprefented at N, ne ale Of onck fhall be explained, 
when 
