1868 The complete Practical Distiller

— SEPARATION OF FECULA.

117

POTATOES

continuous stream of water, proportionate to the dimensions of the sieve, is running in the latter. For a sieve of 2 feet in diameter and 1 in depth, the water may be intro- duced through a pipe of 4 or 5 millimetres in diameter. This water, by means of the movement which the pulp undergoes, penetrates the latter, and runs through the sieve into the tub, carrying the fecula away in a state of dissolution. This operation is continued until the water running through the sieve is clear and not impregnated with fecula. Then the pulp is thrown aside for the T)urpose of feeding cattle, and it is replaced by other, which is in the same manner deprived of its fecula. From 2500 kilogrammes of good potatoes 500 kilogrammes of fecula, supposed to be dry, are obtained, or 750 kilogrammes of drained fecula, which then bears the name of raw fecula. The latter is to the former : : 3 : 2, so that 3 kilogrammes of raw fecula will give 2 kilogrammes of dry; 13 hecto- litres of pulp, or husks of potato, are moreover obtained, which contain about the same quantity of water as the raw potatoes — that is, three-fourths of their weight; so that those 13 hectolitres of pulp retain about 975 litres of water. This pulp may be given to cattle^ but it is by far not so good as that resulting from the distillation of pastes, which is well boiled and nourishing. It might be possible to obviate these inconveniences, in a distillery, by boiling the pulp with the hot spent- wash that is left in the still after distillation. There is a more suitable disposition of the sieve than that just in- dicated, and it is thought necessary to notice it here. It consists in filling at once with water the tub destined to