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equivalent to the bulk of two cubic inches, besides all the carbon contained in 93 inches of carbonic acid.

This carbon amounts in weight to.....12.09 grains. Two cubic inches of oxygen weigh

Total.....

.... 68

.12.77

But as 100 cubic inches of the gas weigh 28.15 grains, it is obvious that besides the 12.77 grains which it furnished to the carbonic acid, it must have contained 15.38 grains of additional matter; but as the only two products were carbonic acid and water, it is plain that the whole of this additional matter must, by the explosion, have been converted into water. Its constituents of course must have been

13.19 oxygen.

2.19 hydrogen,

15.38

Adding this to the 12.77 grains formerly obtained, we get the composition of the gas as follows:

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5. The residue which remained in the retort, after the distillation was over, was a grey powder, not unlike pounded clay slate. To ascertain its constituents, it was dissolved in diluted nitric acid with the necessary precautions; the loss of weight indicated the quantity of carbonic acid. The charcoal remaining undissolved, was allowed to subside, carefully washed by repeated affusions of water, and then dried in a glass or porcelain capsule. It must not be separated by the filter, for it adheres so obstinately that it cannot be taken off the paper, nor weighed, The nitric acid solution was precipitated by carbonate of soda, and the carbonate of lime obtained was violently heated in a platinum crucible. What remained was pure lime.

TO BE CONCLUDED IN OUR NEXT.

On

On the Cultivation of the Poppy for extracting the Oil.

By Dr. COGAN.

From the LETTERS and PAPERS of the BATH and WEST of ENGLAND Society.

ALTHOUG

ALTHOUGH the experiment related in the following letter was made previous to the insertion of the article, concerning the cultivation of the poppy, in our tenth volume *, it is very satisfactory to find, that an English gentleman of respectability has paid some attention to the subject, and proposes to make farther experiments; the result of which must be beneficial, as it will increase our stock of facts, and thus become applicable to some valuable purpose.

Extract of a Letter addressed to Dr. COGAN, by
EBENEZER HOLLICH, Esq.

"When I passed through Flanders in the summer of 1802, I saw several fields of poppies, and learnt that they were grown for the purpose of expressing oil from their seed for food; and that they fed cattle with the refuse or cake. I also learnt that they considered the oils much inferior to that made from olives. I well remember, at the table d'hote at Lisle, hearing a gentleman say, throwing the cruet from him, Ah! it is poppy.' I however, I however, wishing to try it in England, brought a small quantity of the seed over; and on the

* See page 106 of the present volume of this work.

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first of April, 1803, (I think rather too late in the year,) sowed it. I grew enough to enable me to ascertain nearly how much oil a bushel of it will produce. I tried 3 bushels, weighing 1 cwt. 2 qrs. and it produced 6 gallons 2 lbs. of oil, (7 lbs. to a gallon,) and 3 qrs. 25 lbs. of cake; of course 12 lbs. were wasted in the working. It was worked three times over; the first run cold 17 lbs.; the second run cold 19 lbs.; the third rum 11 lbs. was heated. This being so small a quantity, it cannot be quite accurate; nor were we able to have the mill so clean from rape, which it had been just working, as to give it a fair trial. But I am inclined to think, both from this specimen, and from a sample of that oil which my very ingenious friend Mr. Pugh, of Rouen, gave me when I was there, that it by no means is equaľ to fine olive oil for eating; but I question if it might not supply the place of Gallipoli oil, which would be a great acquisition to our manufactories, especially in time of war. And I mean next year to sow a field látely broke up from sainfoin, of about three acres, with it; by which I hope to get seed enough to ascertain its use, and how far it may be worth while to grow it in this country. You will see that my account of the oil produced from a given quantity of the seed differs much from that of Mr. Van Eys. If the sacks mentioned in your paper upon the cultivation of the poppy be four bushels each, I drew much more oil per bushel than he got. As to the cakes, Mr. Eys has given no intimation of their quantity, that is, their weight.

"I found a great difficulty in harvesting the seed. I think we plucked it up, set it upright like beans in the field, and let it stand for some days; and then, brought

it with care to a cloth laid in the field, and beat out the seed, the heads open; therefore if great care be not taken, the sced will be lost.

"You will, I am persuaded, excuse my troubling you with this, and do me the favour to communicate any thing fresh that you may have learnt upon the cultivation or uses of this article. In America, I understand, they grow the large sun-flower to express its oil. I have grown some, but there seems an insuperable objection in harvesting that; at least I have no idea how it can be done.

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According to the above statement it appears, that the poppy oil is less palatable than was represented in the former paper. But as there are various degrees of excellency in the olive oil, this may be the case with the other. It is also probable that the poppy oil may maintain an uniformity more than the olive, which depends greatly upon favourable seasons for its acquiring its pleasant flavour; and without those advantages it may become much inferior to the former. This, however, is merely a conjecture, which future experience alone can confirm or confute.

It is acknowledged that the Dutch, whose domestic consumption of oil greatly exceeds our own, are not so delicate in their taste concerning that article. But as it is an indubitable truth that poppy oil is frequently mixed with the olive by the venders, when sold for culinary purposes, as it will correct the rancidity which

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