| Archangel seed will yield from | 15 to 16 galls. (of 71⁄2 lbs. each) |
| Best Odessa | 18 and even 19 galls. |
| Good crushing-seed | 151⁄2d even 19 gdo. |
| Low seed, such as weighs 48 lbs. per bushel | 131⁄2d even 19 gdo. |
“The average of the seed he has worked, which he represents to be of an inferior quality, for the sake of its cheapness, yields 141⁄2 galls. per quarter. I had some American seed which weighed 521⁄4 lbs. per imperial bushel, ground and pressed under my own observation, and it gave me 111 lbs. oil; that is to say, 418 lbs. of seed gave 111 lbs. oil = 2656⁄100 per cent. A friend of mine, who is a London crusher, told me the oil varied according to the seed from 14 to 17 galls.; and when you consider the relative value of seeds, and remember that oil and cake from any kind of seed is of the same value, it will be apparent that the yield is very different; for example,
| 25th July, 1836, prices of seed. | - | E. India linseed | worth | 52 | s. | per quarter. | |
| Petersburg linseed | 48 | to 52 | do. | ||||
| Odessa | 52 | — | — |
The difference of 4s. must be paid for in the quantity of oil which at 38s. 6d. per cwt. (the then price) requires about 111⁄2 lbs. more oil expressed to pay for the difference in the market value of the seed. Another London crusher informed me that East India linseed will produce 17 gallons, and he seemed to think that that was the extreme quantity that could be expressed from any seed. The average of last year’s Russian seed would be about 14 galls.; Sicilian seed 16 galls.
| Place. | Engine Power. | Hydraulic Presses. | Stampers. | Rollers. | Edge-stones. | Kettles. | Work done,--reduced to an hour. | Number of pressings. |
|---|---|---|---|---|---|---|---|---|
| France | 10 horse power | 1 hydraulic, 200 tons. | 5 light stampers. | 1 pair rolls. | 1 pr. edge-stones. | 5 table kettles small size heated by steam. | 1 English quarter per working hour. | 2 pressings. |
| London | 20 horse power | 1 hydraulic, 800 tons. | 13 light stampers. | 1 pair rolls. | 2 pr. edge-stones. | 8 table kettles small size heated by fire. | 2 English quarters per working hour. | 2 ditto |
| London | 12 horse power, but the engine is used also for other work. | none | 9 light stampers. | 2 pair rolls, used also for other purposes. | 2 pr. edge-stones, used also for other purposes. | 4 table kettles small size heated by fire. | 7⁄8 English quarter per working hour. | 2 ditto |
| Hull | 18 horse engine, old construction. | none | 3 very heavy stampers. | 1 pair rolls. | 1 pr. edge-stones. | 3 double case large size steam kettles. | 11⁄4 English quarter per working hour. | 1 ditto |
| Ditto | 22 horse engine | none | 6 very heavy stampers. | 2 pair rolls. | 2 pr. edge-stones. | 6 double case large size steam kettles. | Not known. | 1 ditto |
“Rape-seed.—I have not turned my attention to quantity of oil extracted from this seed; but a French crusher (M. Geremboret), on whom I think one may place considerable dependence, told me, that
| 31⁄2 | lbs. of | best Cambray rape-seed yielded | 1 lb. oil. |
| 33⁄4 | — | common rape-seed | 1 lb. oil. |
| 41⁄4 | — | com—onpoppy-seed | 1 lb. oil. |
“Rape-seed weighs from 52 to 56 lbs. per imperial bushel.”
The following are the heads of a reference of machinery for a seed oil-mill:—