C *49 ] 
Ditto of the fourth bar, 2 feet 6 inches to 
place where the threads are hooked on, — — 2 ■ •{ 
r 10,000 • I ,, 000 
__ 33 ^ 4 ^ a ] mo ft inches, the fum of the ereateft 
10,000 ^ ° 
expanfion of the feveral bars, increafed by the powers 
of the levers. This is x 30 by the pulley, on the 
axis of which the index is placed, and carried round 
a dial 10 inches diameter. 
I take fomewhat lefs than 4 of the greateft expan- 
fion from freezing to boiling water, to be about a 
medium of the common degrees of heat and cold of 
this climate, which makes one revolution of the in- 
dex. The inward circle, Fig. 2. is divided into 
80 parts, correfponding with 8o° of Fahrenheit’s. 
Each of thefe is divided into 5 parts on the outward 
circle, one of which is as large as 2 0 #f Fahren- 
heit’s. 
I have compared this inflrument with a mercurial, 
and fpirit thermometer along with it, for fome time 
pad: 5 and have obferved, that it conftantly begins to 
mark the change before either ; though the mercury, 
in fome time, when the room beeomes warm by 
hre, or otherwife, rifes a degree or two above it. 
When the room is warmed to any great degree, it 
rifes fomewhat higher than the mercury, and, at the 
lame time, the fpirit rifes higher than either, though, 
on the firffc degree of warmth, it does not rife as fall 
as either. 
The metalline thermometer has this advantage 
over any other, that its range may be increafed to 
any degree intended. I have one which carries the 
index 72 inches, by the common changes of the 
weather, which may be raifed 50 or 6 o°, by blowing 
one’s 
