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val, a fresh portion of this faccha-
rine matter, which was exactly fi-
milar to that already spoken of.

V. Having thus provided my-
felf with a certain quantity of this
kind of fugar, I tried various me-
thods to make it take a regular
cryfialized form; but in that re-
fpect, all my trials were in vain.
Whether I ufed the pureft fpirit of
wine, or water, to diffolve this
fubftance, the refult was the fame.
I remarked, indeed, that the fo-
lution of it in water, which had
been thickened to the confiftence
of fyrup, depofited, after fome
time fmall knobs on the fides of
the veffel, which had the form of
cauliflowers; the whole folution
afterwards coagulated, and appeared
like a folid, dry, white mafs, full
of fmall cavities, which, when ex-
amined with a microfcope, feemed
to be compofed of very fall long
cryftals, extremely thin, and hardly
vifible to the naked eye.

VI. Though this manner of cryf talyzing fufficiently diftinguishes the faccharine part of honey from common fugar, I fufpected, at firft, that this difference proceeded only from the prefence of fome heterogeneous parts, from which the honey was not fufficiently cleared; but the following experiments evidently fhewed, that thefe two fubftances differ from each other by properties which are very strongly marked.

1. If a certain quantity of limewater is added to a watery folution of the fugar of honey, it inftantly acquires a brown colour, though it was before quite limpid and colourlefs.

2. Quick lime, which I added to the watery folution of fugar of

honey, while it was upon the fire, produced a very ftrong effervefcence, and the mixture immedi ately became of a dark brown colour, almoft black. ing to add quick lime until the By continu effervefcence ceafed, the fugar of honey was entirely decompofed; the mixture turned quite black, and emitted a fmell which was very difagreeable, and even naufeous.

contains a large quantity of lime, 3. The dark coloured folution which cannot be precipitated by means of aerated alkali, nor by an alkali rendered perfectly cauftic.

to precipitate this lime, it then 4. If vitriolic acid is made ufe of appears in the form of gypfum; but the remainder of the liquor ftill contains a very empyreumatic acid, which feems to have a ftrong analogy with the malic acid of Scheele.

is treated with nitrous acid, it is 5. If the acid of fugar of honey converted into acid of fugar.

be obtained by making use of a 6. A much more pure acid may double affinity. For this purpose, it is only neceffary to boil together equal parts of honey and quick lime, in a great quantity of water, adding to this folution, which is of a brownish colour, as much charcoal-powder as may be requi fite to take away the colour enfiltered, and to the clear liquor tirely. The folution must then be must be added a very faturated folution of lead in diftilled vinegar, until all precipitation has ceated. The precipitate obtained by thefe means must be washed in fuch a quantity of water as will edulcorate it thoroughly; after which, as

much

much diluted vitriolic acid must be added as may be fufficient to feparate the acid of the honey from the lead this acid may then be concentrated by evaporation.

7. If the folution of honey and quick lime is thickened by evaporation, after its brown colour is taken away by charcoal, a tranfparent mafs, of a light yellow cofour, is produced, which refembles gum arabic; it has a bitter tafie, and does not grow moift by being expofed to the air.

8. The clear mats which is produced from a mixture of the acid of honey and lime is perfectly infoluble in fpirit of wine; and it may be precipitated from its folution in water by this fpirit.

9. Cauftic fixed alkalies produce upon honey, and upon the fugar which is procured from it, the fame effect as lime. Honey, as well as its fugar, is entirely decompofed by them; and always with a very violent effervefcence. The dark coloured extractive mafs which is obtained by thefe means is completely infoluble in fpirit of wine; and, when the quantities of the two fubftances are exactly proportioned, very little tatte can be perceived in the mafs; that little is by no means alkaline, and can hardly be called faline. This proves that alkalies, as well as quick lime, may be perfectly faturated by the acid contained in honey.

10. Volatile alkali alfo decomposes honey in the fame manner, and with the fame circumftances, as other alkalies; but this decompofition takes place much more lowly, and only when heat is at the fame time made ufe of.

VII. That conftituent part of honey which is got from it by treating it with the fpirit of wine (III.)

may be diftinguished from the fu gar of 'honey, by the following property, viz. that it cannot be reduced into a dry or folid form. It is owing to this particular part that the folution of honey fo readily contracts a brown colour; for a folution of fugar of honey, deprived of this glutinous part, may be thick ened upon the fire without fuffering any alteration of colour. In other refpe&s, the yellow glutinous part of honey, here spoken of, thews nearly the fame properties as the fugar of honey; and when treated with cauftic alkalies, or with quick lime, its tafte is alfo the fame.

VIII. The properties which I have above defcribed are thofe by which the fugar of honey differs eflentially from common fugar. If this laft is treated like honey, it exhibits the following refults.

1. Neither quick lime nor fixed alkalies produce any decompofition in fugar; no effervefcence is obferved, nor does the folution thew any change of colour.

2. Whatever quantity of fugar is added to fixed alkalies, they always preferve their caufticity; and, even if they are boiled with fugar for a confiderable time, they never appear to be united with its acid.

As quick lime, when combined with fugar, is attended with fome phænomena which appear not to have been taken notice of by any perfon, I fhall here mention them.

By boiling together equal parts of fugar and quick lime, in a fufficient quantity of water, a folution is obtained, which, by the furprifing quantity of lime it contains, may be confidered as highly-faturated lime-water, in which the tafte of the fugar is not to be perceived.

, By

By evaporating this folution to drynefs, a white tenacious mass is obtained, which has fuch an acrid and burning tafte as to affe&t the tongue like caustic alkalies.

3. By expofing a folution of lime and fugar to the air, after having been filtered into an open veffel, the furface becomes gradually covered with a great number of fmall cryftals; these are fucceeded by others whenever, by fhaking the liquor, the first formed ones are made to fall to the bottom of the veffel. This formation of cryftals at the furface continues till the liquor contains no more lime; then the fugar again acquires its proper tafte.

4. The fmall crystals, of which I have juft fpoken, very readily lofe their water of cryftalization,by being exposed to the open air; according to my experiments, I fhould confider them only as an aerated calcareous earth cryftalized.

5. One of the most remarkable properties of the filtered folution of lime and fugar is, that by being made to boil, it foon grows turbid and thick; the lime then falls to the bottom of the veffel, and this precipitate is of a milk-white colour; but as foon as the folution grows cold, the lime again diffolves in it fpontaneously, and the folution becomes once more as limpid and tranfparent as it was at firft. This phænomenon (which it is rather difficult to explain) was obferved by M. de Laffone, when,

in the fame manner, he combined the neutral falt of tartar with quick lime. (See Memoirs of the Academy of Paris, 1773, page 191.)

6. Alcohol, or very highly rectified fpirit of wine, precipitates the lime from the forementioned folution.

7. Mild alkalies, by the aerial acid they contain, produce the fame effect.

8. Cauftic alkalies do not cause the fmalleft alteration in the folution.

IX. From what I have faid it follows,. that the union which exifts between the faccharine part of honey and the oily part is much weaker than the union between the fame parts in fugar. This laft cannot be decompofed, in the humid way, except by treating it with nitrous acid; while honey and the fugar it contains, may be decompofed, not only by that acid, but alfo by mild alkalies, and by lime.

Upon the whole, there appears very little reafon to hope that we fhall ever be able to obtain honey in the form of fugar; to bring it into that form, fomething more than a mere feparation of its heterogeneous parts feems neceffary. It is indeed faid, that, in fome kinds of honey, efpecially in that from Narbonne, crystals of fugar, completely formed, have been obferved; admitting the fact, I confider it only as an accidental circumftance.

USEFUL

USEFUL PROJECTS.

Firft report from the felect Committee appointed to take into confideration the prefent high price of Corn.

THE felect committee appointed to take into confideration the prefent high price of corn, and to collect evidence relative thereto, and to report the fame, from time to time, as it fhall appear to them, to the house, with their obfervations thereupon, proceeded, in the first instance, to confider fuch in formation as had been already collected concerning the fame.

They examined, for this purpofe, the minutes of the evidence taken before the lords of his majefty's privy council, upon this fubject. They received from fir John Sinclair, one of the members of the committee, the fubftance of fuch accounts of the state of the late crop of grain, as the correspondence of the board of agriculture had enabled them, at the prefent period, to collect. They had further the opportunity of receiving from many of their members a statement of facts within their own knowledge or communicated by refpectable authorities from their different counties.

They have received alfo from his majefty's principal fecretary of ftate for the home department, fuch returns as had been hitherto made to the circular letter written by him, by his majefty's command, to the

cuftodes rotulorum and fheriffs depute in England and Scotland, defiring them to obtain meetings of the magiftrates for the purpose of procuring an account of the state of the late crop but these returns are not as yet fufficiently numerous or complete to lead to any precise conclufion.

On the whole, however, the general information derived from the fources above-mentioned fatisfied your committee, that the crop of other forts of grain than wheat has been upon the whole abundant, but that the produce of wheat has proved fo far deficient, as to require the adoption of the fpeedieft and moft effectual measures for the remedy or alleviation of fo great an evil. They were therefore of opinion, that they should best perform their duty by directing their immediate attention to the confideration of fuch measures; and have, on that account, deferred for the prefent pursuing a detailed inquiry into the exact amount of fuch deficiency; but they propose to report the fame more particularly to the house, when they fhall have received fuch further information as may enable them to collect more fully the general opinion, upon a point which they are sensible it is impoffible at any time to afcertain with any great degree of accuracy.

The first and moft obvious mode

of

of fupplying this deficiency is, the importation of grain from foreign parts-and for the purpose of forming an opinion as to what may be the profpect of fupply from thence, and the most expedient means to be adopted for procuring it, your committee proceeded to examine fuch perfons, from whofe knowledge and experience in the trade of corn they could expect the beft information. It appeared from their concurrent teftimony, that, though the crop of wheat in the United States of America, and in the countries bordering upon the Mediterranean, was reprefented as abundant; and in the northern and eastern parts of Europe as not materially deficient; yet, as the old ftock was much exhaufted, and the demand great, the price, according to the laft advices, was eve ry where uncommonly high. But, though there was upon this point fome difference of opinion, it appeared upon the whole very doubtful whether a fupply to any confiderable extent could be depended upon from foreign parts, whatever measures might be adopted. Your committee next proceeded to in-, quire what meafures, in the judgment of thefe perfons, afforded the beft probability of obtaining fuch a fupply. They thought it right to bring diftinctly under their confideration the alternative of leaving the whole care of fuch purchases to the executive government, who would (it was conceived) be in fuch cafe the only purchafers, and be publickly known to be fo; or of leaving the fame to the fpeculation of individual merchants, encouraged by a liberal bounty on importation, and by a public declaration on the part of government

(as foon as fuch declaration fhall be practicable) of the quantity which they may then have at their difpofal in confequence of former orders, and of their intention to give no further orders for the purchafe of corn, and to fell what may have been procured in limited quantities, and at the market price. It appeared to your committee to be the preponderant opinion amongst thofe perfons to whom this alternative was ftated, that, upon the whole, the reftoration of the trade in corn to its natural channel, with the additional encouragement of a bounty, was the moft eligible mode of endeavouring to procure from foreign parts fuch fupplies as thofe markets might be found able to furnish. Your committee were further confirmed in this opinion by the information they received from fome of their members, that there were merchants who had ftated to them their readinefs, under those circumftances, to engage in fpeculations to a large extent. full confideration and difcuffion of this important point, your committee were of opinion, "that it was expedient for the executive government to defift from making any further purchases of corn; and that a bounty fhould be granted upon the importation of certain forts of grain into this country, for the encouragement of private fpeculation."

After a

Your committee next proceeded to the confideration of the amount and diftribution of fuch bounty. They had been informed that, from the abundance of the crop of wheat in the countries bordering upon the Mediterranean, there might be a confiderable difpofeable furplus

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