184 W. P. Riddell on Soleil’s Saccharimeter. 
ing tube, as this greatly facilitates a speedy filtration. The same 
bone-black may be used several times, if care be taken to rinse 
and dry it after each operation. It has been found also, that its 
qualities may be in a great measure restored by burning anew. 
Analysis of Canes.—F rom M. Clerget’s memoirebefore men- 
tioned, I translate, in substance, the following: weigh 200 
grammes of the cut cane, and extract the juice therefrom by 
means of the small special press, endeavoring to make the pres- 
sure as near that exerted by the common sugar presses aS possi- 
ble, in order that the juice may be a fair representative of that 
ustially extracted in the manufactories; from this juice fill the 
graduated matrass to the mark indicating a capacity of 100c.¢.; 
to this add 10 ¢.¢. of the defecating agent as in the analysis of 
sugar and molasses; filter and introduce it into the tube of ob- 
servation 22 centim. long: take the degrees of variation, which 
multiply by 164-71 and divide the quotient by 100 and you will 
have the number of grammes of sugar contained in a liter of the - 
juice; the caleulation may be dispensed with by referring to ‘the 
number expressing degrees of deviation in the column of the 
table marked A, and seeking the corresponding ones of the eo! 
umn marked B, which will give the number of grammes per liter 
contained in the juice. 
now, by means of a very delicate areometer graduated to 
the 10th of a degree, we take the density of the liquid, we MaY 
infer from a very easy comparison between this density, the sae 
charimetric title of the juice and the weight of the pressed cane, 
the actual per cent. of the real sugar contained in the juice to the 
weight of the original cane: for example, a specimen of * 
grammes of Tahiti cane cultivated in the Antilles was submitted 
to the action of the small presse d’essai, and left a pulp weighing 
48 grammes; it consequently produced 152 grammes of juice, © 
which the density was found to be 1089-5; this juice observed 0 
means of the saccharimeter gave a deviation to the rig t of 12 : 
multiplying this number by 164-71 and dividing the progv™ 
by 100, the quantity of sugar per liter was found to be 2 8 
24 c¢., which is the étle which we also find in the column ut 
opposite 124° in the column A. Then we have 1085 (wels ) 
of a litre of the juice) : 204-24 (weight of the sugar per litre) 
+11:0°1882 (the per cent. of the sugar compared to the juice) 
—and 0:1882 multiplied by 152 we obtain the total — 
the sugar extracted by simple pressure from the 200 g's. © bf 
cane, that is, 28 er. 60.¢., or 14°30 per cent. of the weight 
the cane. | oe 
In the analysis of fresh cane juice, it is not usually neces) 
to perform the operation of inversion—a process which must 
be omitted in the examination of molasses and impure 
sugars. et . 
