26 
THE ELA10METER. 
oil of poppy seeds jvvhen mixed with olive oil, and of the 
proportions in which these two are present. 
This process consists in the use of an instrument which 
I have called the eldiometer, the construction of which is 
founded on the difference between the densities of olive 
oil and oil of poppies. This instrument is an areometer, 
having a large bulb surmounted by a very small tube. In 
consequence of this construction, the instrument is one of 
extreme sensibility. It is graduated so that at a tempera- 
ture 10° Reaumer, or 12.5 C. (55° Fahr.) it rises to in pure 
oil of poppy-seeds, this being the greatest density indicated ; 
and to 50 in pure olive oil, this being the least density indi- 
cated. The interval between and 50 is divided into fifty 
equal parts. The is marked at the bottom of the stem, 
and the 50 at the top. 
I have graduated the instrument at a temperature of 55° 
Fahr., because this is the usual temperature of the cellars in 
which the oil is kept. 
If, on immersing the instrument at 55° Fahr., the stem 
sinks to the point marked 50, it may be inferred that the 
oil is pure ; but if, on the other hand, it does not reach this 
point, the inference will be that the oil is mixed. 
If the instrument stands at 40, this number multiplied 
by two, will give the quantity of pure olive oil present in 
100 parts; the sample, in this case, being mixed with 
twenty per cent of oil of poppy-seeds. In like manner, any 
other number below 50, at which the instrument floats, 
will, by the same process, indicate the amount of adultera- 
tion. — Lond. Pharm. Jour., from Jour, de Pharm. 
