On Specific Gravity. 129 
may be. discovered by means of the second bucket, which 
gives fifths for each measure of water ; which, if added to - 
the outer bucket, would be equivalent to a whole number. 
By the eye, the distance is equally so divided, as to give half 
fifths, or tenths. Or, the nearest bucket, being hung one half 
nearer the fulcrum, the same measures will become tenths in 
the latter, which would be units, if added to the outer bucket. 
Rationale. 
The portion of the rod, marked off by the band, was_evi- 
dently found competent by its introduction into the tube of 
the chyometer, to exclude from the orifice a weight of water, 
pe to Paarbea the resistance encountered by the min- 
eral in sinking i : consequently, eably to the gen- 
eral rule,* to find the eres gravity of heat a we fave 
only to find how often this weight (of water) will go into the 
weight of the mineral—or, what is the same in effeet, how often 
the former must be taken, in order to balance the latter. In- 
deed, it must otherwise, be sufficiently evident, that the min- 
and the water being made equal in weight, their specific 
aus must be inversely as their bulks, which are known 
by the premises. 
The inner bucket may be dispensed with, and greater frac- 
tional Piatti attained, by means of a sector, graduated in- 
to 100 parts. It is for this purpose that the sliding band, 
and the ferrule at the but-end of the tube, are severally fur- 
mished with the points. The assistance of a sector is espe 
cially applicable, where fluids are in question, since it is ne- 
cessary to find their differences in thousandths. 
To find the specific SOBEL 0 4 ofa hod, by the Sectoral oe 
Let a glass bulb, (represented in figure 5, under dhe bucks 
ets,) be suspended from the outer bucket, and es ep 
Let the situation of the beam be marked, by bringing ‘the 
point of the index opposite #6 ck Let the tube of the chy- 
ometer be full of water, and the rod retracted, until stopped 
by an enlargement purposely made at its inner termination. 
Next return it into the tube, until as much water is 
into the bucket, as is just adequate to cause the immersion of 
* See page 121. 
VOL. L—NoO. 1. 17 
