POTATO STARC11 may be roughly made thus: Put a pound and a quarter of potatoes, grated through a common tin bread grater, into a pan of water, and stir with a wooden spoon, and as soon as the pulpy matter has subsided, the dis colored water is poured off, and clean water added, and the mass again stirred up. When it has settled a second time, the water is poured off by a gentle incli nation of the vessel, and the process re peated till the water passed off is color less. Three washings are sufficient. The residue is turned out of the pan, and dried in the air, and it produces four ounces of very fine white flour, or one fitth of the original weight of the pota toes. It may be used as a substitute for arrow-root, for years. A bread-grater is the only instrument necessary.
Potato flour, and Arrow-root flour.— Potato flour may be known from arrow root flour, by rubbing a little of it be tween the finger and thumb, when it will be observed that the potato flour is softer to the toads, and more shining to the siglst, than arrow-root.
Size from Potatoes.--Starch of potatoes, quite fresh, and washed only once, may be employed to make size ; which, mixed with chalk, and diluted in a little water, forms, a very beautiful and good white for ceilings. This size has no smell, and is more durable.
Potato starch is manufactured exten sively in this country, in Maine. The following account of a starch manufacto ry in Michigan, at Almont, Lopez coun ty, will illustrate the mode in which it is usually made here. It is probably the largest establishment of the kind in the United States, and is owned by a gentle man who is also interested, it is said, in two others in Vermont. It is quoted from the Patent Office Report.
"The factory is 214 feet long and 40 wide, including an L. The main build ing is 134 feet long, 14 of which are used for an engine room, and is two stories high. The lower part has 64 tubs, hold ing about 600 gallons each, giving a total of 28,400 gallons. The L part is 80 feet long by 40, of brick, one and a half sto ries high, for a potato bin. Loaded teams drive up a platform into the second story, and following a circle, 18 teams can unload at a time, through a trap door over the bin, which is calculated to hold 40,000 bushels. One hundred and thirty loads have been received in a day, mak ing a total of 4000 bushels.
" In the second story of the principal building is an oven 100 feet long by 18 wide, for drying the starch ; or rather, I should say, an oven of 200 feet by 9, as there is a division in the centre, with doors some ten feet apart. In the oven
there arc sets of pans, one above the other, which can be turned at pleasure. It is heated from the steam works, and conductors of heat are carried in tin pipes all over the building.
' The potatoes are shovelled from the bin into a hopper, where there is water constantly running into it, and where they are as thoroughly washed by ma chinery as a cook could do it for your dinner. Then, by the action of the ma chinery, they are separated from the dirt, stones, and sticks, and pass on to two cylinder graters, at the rate of 100 bush els an hour. From graters, by the action of the machinery, they go into the sieve, that separates the starch from the potato. The pulp then passes into four large cisterns, and there again machinery pumps it into the 64 large tubs or cis terns, before alluded to, for settling. Then the water is drawn off, and the starch, by a forcing pump, is carried into the second story, and, wheh settled, put into the oven I have before spoken of, which • is calculated to bake a day's work, being the starch from 1000 bushels or 60,000 lbs. of potatoes. The starch is packed in casks and shipped east. The cost of the factory is- $12,000.
"Considerable starch was made in the season of 1846, but the rotting of some 80,000 bushels that fall curtailed the quantity anticipated. This large quan tity of the raw material was thrown away. It served to feed many cattle and hogs of the neighborhood for some mouths. Thepulp remaining as worth less is used in fattening hogs, which the proprietor has in a yard adjoining.
" The factory price for potatoes is ten cents a bushel. The owner has contract ed with various farmers to the amount of 400 acres. The average number of bushels raised in the year 1846 on an acre, was 275. Allowing the same this year, it will amount to over 100,000 bush els ; but this is not half the quantity wanted. Farmers are unwilling to con tract, fearing the rot. Present indica tions are good for the crop. All varie ties are used—even the Rohan.
"It takes the fall and winter to use up the potatoes ; then wheat and corn are used for the same purpose. The made from the potato per year will not be far from 1,000,000 lbs. or 500 tons. It sells for $5 a hundred in New York."