124 
SELECTED ARTICLES. 
a single precaution, may render the whole operation unsuc- 
cessful; much more syrup altered by sulphuric acid is sold for 
syrup of dextrine than is thought. But all the conditions ne- 
cessary to full success in this operation, are not yet prac- 
tised in manufactories. I will briefly enumerate them: 1st, it 
is better to employ a small proportion of sulphuric acid, and 
to prolong its action, but it must not be saturated until the 
transformation is complete; this may be ascertained by pour- 
ing into a small quantity of the fluid, about three times its 
bulk of alcohol; no precipitate should take place; 2d, the ex- 
cess of acid must be saturated as soon as the transformation is 
complete, for if suffered to remain, it reacts on the sugar; 3d, 
the use of steam is much preferable to that of fire; 4th, the 
saturation and clarification demand particular attention; it is 
here that most manufacturers fail; if too much lime be added 
to saturate the acid, the sugar is rapidly blackened and alter- 
ed; it is therefore better to leave the syrup somewhat acid 
than to overstep the mark. The choice of a substance to cla- 
rify the syrup much embarrasses manufacturers; some employ 
animal charcoal; others black schist; others again a mixture of 
both; but always with different results; some maintain that 
these agents contain either small portions of lime, or alkali, or 
sulphurets, and very minute quantities of either are sufficient 
to colour the syrup during evaporation, and to injure its crys- 
tallization. I have always employed with the greatest suc- 
cess the charcoal resulting from the action of potash on blood 
or horns, as furnished by the makers of Prussian blue; this 
should be first treated with muriatic acid and then thoroughly 
washed with water. This charcoal has a powerful decolour- 
izing effect on starch sugar and may be purchased at a low 
rate, as the manufacturers have no sale for it, except as a ma- 
nure. 
By following the above rules, a beautiful sugar may be 
made, well crystallized, very white, having a purely sweet 
taste, and containing no uncrystallizable sugar. 
Journ. de Pharm. 
