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423

OF STARCH GAGING.

Starch is generally made of the meal of corn, put into a Vat with a sufficient quantity of water, in which state fermentation is suffered to go on for seven or eight days, according to circumstances and the state of the weather. As soon as the fermentation is complete the finest part of the flour settles at the bottom of the Vat, from which it is removed in small quantities at a time, and placed in hair sieves, where it is washed to separate the Starch from the bran. In this process the fine matter runs through the sieves with the water into the Frames or Tubs, and the water thus impregnated with Starch is called a Sour Water.

In two or three days the Starch settles at the bottom of the Tub or Frame, and then the water is decanted off. The Starch is now washed with a fresh portion of water, and the washings containing the coarse slimy part of the meal or flour is put into another Frame, and denominated a Slime.

Clean water is now poured on the remaining pure sediment, and the whole is stirred and passed through a finer sieve into another Frame to settle, and in this state it is termed a Green Water.

When a Green Water has stood two or three days, the Starch deposits itself at the bottom of the Frame, where it is collected and boxed.

Sometimes the Starch which has settled at the bottom of a Green Water is again washed, when the water employed for this purpose is, when impregnated with Starch and decanted into a Tub or Frame, called a White Water.

As soon as the Starch at the bottom of a Green Water is thought sufficiently cleansed from impurities, it is taken out, and disposed of in Boxes with holes in the bottom to drain and harden; and when sufficiently hardened it is taken from the Boxes, and broken into pieces to be dried on bricks. After drying, it is put into a stove to crust, and the crusted part being afterwards scraped off, the pure part is papered, labelled, and stamped. In this state it is again placed in a stove to dry, and when dry is taken out and weighed in the presence of the officer appointed for that purpose.

The instruments used in Starch Gaging, are, besides a dimension-cane and tape, a spit inched and tenthed, a brass plate to screw to the end of the cane, and a spatula for examining the Starch in the utensils during the process of making.

PROBLEM I.

To Gage and Tabulate a Starch-Maker's Vat.

Take the dimensions precisely in the same way as directed for a Maltster's Cistern, and find the area in square inches. Then divide the area in inches, by 2828, the number of cubic inches into which a bushel

of meal resolves itself on charging the Vat, and the product will be the area in bushels of the raw materials. The area in bushels, multiplied by the depth, will be the content in raw bushels. For a circular Vat, the square of the diameter divided by 3601 will give the area in bushels, without finding it in inches.

By experience it is ascertained, that every bushel of meal on an average gives 25 pounds of Green Starch, and consequently any number of bushels multiplied by 25, will give the pounds equivalent to that number of bushels.

EXAMPLE.

Given a rectangular Vat 200 inches in length, and 141.4 in breadth, to find the area in bushels, and in pounds.

SOLUTION.

141.4 breadth

200 length

2828) 28280.0 (10 area in bushels.
Multiply by 25 pounds in a bushel

Product 250 area in pounds.

This area multiplied by the depth of the Vat, whatever it may be, will give the whole content of the Vat in pounds of Green Starch.

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A Starch-Maker's Vat is tabulated in the same manner as a Brewer's Copper, by continually subtracting the area from the whole content for dry inches, because the gage is always taken for the distance of the top of the settlement from the level of the mouth of the Vat.

It seems unnecessary here to give a specimen of a Dimension Book, or to enlarge further on this subject, as every officer, whose duty leads him to visit StarchMakers, is furnished with ample instructions for his guidance in every particular.

PROBLEM II.

To Gage a Starch-Maker's Water Frame.

From several lengths in various parts of the Frame deduce a mean length; so in like manner a mean breadth, and a mean depth: then multiply the mean length by the mean breadth, and divide by the proper divisor, in the Table of Factors, Divisors, and Gage Points, for Green Starch pounds, given in page 142 of this work the quotient will be the area of the Frame, and this multiplied by the depth will give the content.

A Table of the Frame may evidently be constructed by continually subtracting the area from the whole content of the Frame; but as the sediment in either a Sour Water or Green Water seldom reaches within 12 inches of the top of the Frame, it is customary to deduct 12 times the area from the content before the tabulation is begun. This deduction may be more conveniently made by taking away 12 inches from the depth of the Frame, for the area multiplied by the remainder will be the content of 12 dry inches.

To render this plainer, we shall suppose the length of a Water Frame to be 233-8 inches, the breadth 52 inches, and the depth 32 inches, the operation of finding the area and commencing the tabulation will be as under.

233.8 length of the frame

52

4676 11690

34.8) 12157-6 (349.3 lb. area in green starch Depth 32-12 = 20

Product 6986 lb. content at 12 dry inches.

As the content at an inch deep is 349-3 lb. the content at half an inch will be 174-65 lb. Wherefore, a Table for every half inch beyond 12 inches may be constructed by continually subtracting 174-65 lb. from 5986lb. the content of the Frame at 12 dry inches. Thus,

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