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" TABLE II. , Binary Proportions of Oxygene and Nitrogene in Nitric
and Nitrous Acids*.
Proportivas. Nitrogene. Vaity.
2,389 Bright yellow Nitrous 70,10 29,90
2,344 Orange coloured 69,63 | 30,37
2,292 Dark green
| 69,08 | 30,92 13 i | 2,230 The second section commences with the following paragraphs :
- The formation and decomposition of volatile alkali in many procelles, was observed by Priestley, Schecle, Bergman, Kirwan, and Higgins; but to Berthollet we owe the discovery of its constituent parts, and their proportions to each other. These proportions this ex-, cellent philofopher deduced from an experiment on the decomposition of aëriform ammoniac by the electric spark: a process in which no apparent source of error exists.
" Since, however, his estimations have been made, the proportions of oxygene and hydrogene in water have been more accurately deler. mired. This circumstance, as well as the conviction of the impollia bility of too minuiely scrutinizing facts, fundamental to a great inass of reasoning, induced me to make the following experiments." P. 56.
This is followed by the narration of the experiments, the result of which is, that the nitrogene in ammoniac is to the hydrogene, as 35 to ros in volume ; and 13,3 grains of ammoniac are composed of 10,6 nitrogene (supposing that 100 cubic inches weigh 30,45 grains) and 2,7 hydrogene.
In the same section, we also find an examination of the specific gravity of ammoniac ; an investigation of the quantity of ammoniac in different aqueous solutions; and various other particulars concerning ammoniac.
Iris somewhat singular, that in certain places this author still seems to entertain the idea of phlogiston, and accordingly says, that certain substances are dephlogisticated or phlogistis cated, when almost all other philosophical chemists would say, that those substances are oxygenated or deoxygenated. Buc there is a singularity of style observable throughout the work. Speaking of the non existence of ammoniacal nitrates, “I acteinpted," this author says, “in different modes to combine nitrous acids with ammoniac, so as to form the salts which
“ * Nitrous gas contains 44,05 nitrogene, and 55,95 oxygene, as has been said before.”.
lates fomed exiishich have
have been supposed to exist, and called nitrites of ammoniac ; but without success.” He then relates some experiments, and concludes that no substance properly so called exists.
The third Division contains the principal facts which have been ascertained concerning the production, the specific gra. vity, and other properties of the nitrous oxide. The very curious nature of those properties, induces us to transcribe fuch passages of this Division, as may give our readers a competent idea of the subject.
" ift. Compact, or dry nitrate of ammoniac, undergoes little or no change at temperatures below 260°.
“ zdly. Ai temperatures between 2759 and 300°, it slowly sublimes, without decomposition, or without becoming Auid.
“ 3dly. At 320° it becomes fluid, decomposes, and Rill Nowly sublimes; it neither assuming, or continuing in, the fluid ftate, without decompofition.
" 4thly. At temperatures between 3400 and 480°, it decomposes rapidly,
" sthly. The prismatic and fibrous nitrates of ammoniac become fluid at temperatures below 300°, and undergo ebullitions at temperatures between 360° and 400°, without decomposition.
" 6thly. They are capable of being heated to 430° without decomposition, cr lublimation, till a certain quantity of their water is evaporat...
"penly. At temperatures above 4500 they undergo decompofition, without previously losing their water of crystalisation.” P. 85.
« Two hundred grains of compact nitrate of ammoniac were introduced into a glass retort, and decomposed Nowly by the heat of a spirit lamp. The first porsions of the gas that came over were rejected, and the last received in jars containing mercury. No luminous appearance was perceived in the retort during the process, and almost the whole of the falt was resolved into Avid 3.nd gas. The fluid had a faint acid taste, and contained some undecompounded nitrate. The gas collected exhibited the following properu.es: .
"a. A candle burnt in it with a brilliant flame, and crackling noise. Before its extinction, the white inne:r flame became furrounded with an exterior blue one.
« b. Phosphorus introduced into it in a state of inflammation, burnt with infinitely greater vividness than before.
"C. Sulphur introduced into it when burning with a feeble blue Rame, was instantly extinguished; but when in a state of active in. flammation (ihat is, forming sulphuric acid) it burnt with a beautiful and vivid rose-coloured flame.
" d. Inflamed charcoal, deprived of hydrogene, introduced into it, burnt with much greater vividness than in the atmosphere.
"c. To some fine twisted iron wire a small piece of cork was af. fixed : this was inflamed, and the whole; introduced into a jar of the air. The iron burned with great vividness, and threw out bright fparks as in oxygene,
uf. Thirty .
«f. Thirty measures of it exposed to water previously boiled, was tapidly abforbed; when the diminution was complete, rather more than a measure remained. .
“ę. Pure water saturated with it, gave it out again on ebullition, and the gas thus produced retained all its former properties.
“ h. It was absorbed by red cabbage juice; but no alteration of colour took place.
i ;Its taste was distinctly sweet, and its odour sight, but agreeable.
" ;. It underwent no dimination when mingled with oxygene, or nitrous gas." P. 86. .
• We may conclude, that 100 cubic inches of pure nitrous oxide weigh 50,1 grains at temperature 50', and atmospherical pressure 37.
867 I was a little surprised at this great specific gravity, particularly as I had expected, from Dr. Priestley's observations, to find it less heavy than atmospherical air. This philosopher supposed, from some appearances produced by the mixture of it with aëriform ammoniac, that it was even of less specific gravity than that gas."
“ Thus in nitrate of ammoniac, four affinities may be supposed to exift.
" 1. That of hydrogene for nitrogene, producing ammoniac. "s. 2. That of oxygene for nitrous gas, producing nitric acid.
“ 3. That of the hydrogene of ammoniac for the oxygene of ni. tric acid.
“4. That of the nitrogene of ammoniac for the nitrous gas of nitric acid.
" At temperatures below 300', the salt, from the equilibrium between these affinities, preserves its existence.
« Now, when its temperature is raised to 400°, the attractions of hydrogene for nitrogene, and of nitrous gas for oxygene, are diminished; whilft the attraction of hydrogene for oxygene is increafed ; and perhaps that of nitrogene for nitrous gas.
“ Hence the former equilibrium of affinity is destroyed, and a new one produced.
« The hydrogene of the ammoniac combines with the oxygene of the nitric acid to generate water; and the nitrogene of the ammoniac enters into combination with the nitrous gas to form nitrous oxide: and the water and nitrous oxide produced, moft probably exift in bia nary combination in the aëriform ftate, at the temperature of the dea composition.
« But when a heat above 800° is applied to nitrate of ammoniac, the attractions of nitrogene and hydrogene for each other, and of oxya gene for nitrous gas, are still more diminished ; whilst that of nitrogene for nitrous gas is destroyed, and that of hydrogene for oxygene increased to a great extent : likewise a new attraction takes place; that of nitrous gas for nitric acid, to form nitrous vapour. Hence a new arrangement of principles is rapidly produced ; the nitrogene of ammoniac having no affinity for any of the single principles at this temperature, enters into no binary compound : the oxygene of the nitric acid forms water with the hydrogene, and the nitrous gas combines prith the nitric acid to form nitrous vapour. All these fubftances molt
probably exist in combination at the temperature of their production; and at a lower temperature, assume the forms of nitrous acid, nitrous gas, nitrogene, and water." P. 114.' · Having transcribed so much of this interesting Division, we shall endeavour to be more concise in our account of the remaining part of this work.
The fourth Division contains a variety of experiments, tend. ing to manifest the components of nitrous gas. This gas was decomposed, both by means of charcoal, and by means of phosphorus; whence it appeared, that 100 parts of nitrous gas contain 53,4 of oxygene, and 46,6 nitrogene. In the same Division we find the narration of several experiments concerning the absorption of nitrous gas by water, as also by certain saline solutions.
The opinions of Priestley and Kirwan on the converfion of nitrous gas into pitrous oxide, are examined in the fifth Divi. sion; to which this author fubjoins some of his own experimenis and observations on the same subject.
The first Division of the second Research, contains experi. ments and observations on the combinations of the nitrous oxide with various fluids, both elastic and non-elastic ; as also with the three alkalies. The particulars are numerous, but not very interesting.
The contents of the second Division are more deserving of attention; but, with respect to them, we must refer qur readers to the work itself.
The third and fourth Researches contain the most useful part of the subject ; namely, the application of nitrous oxide to the animal body. They ihow how far it may be respired, and what changes it produces in the body, as well as what changes the gas itself undergoes.
The experiments which are described in the sequel, were made by confining warm-blooded animals in jars full of the nitrous oxide. This gas was produced from nitrate of ammoniac, and was received into jars filled with water previously saturated with that gas. The following conclusions were derived from those experiments.
"1. Warm-blooded animals die in nitrous oxide infinitely sooner than in common air or oxs'gene; but not nearly in so short a time as in gases incapable of effecting positive changes in the venous blood, or in non-respirable gases.
“ 2. The larger animals live longer in nitrous oxide than the smaller ones, and young animals die in it fooner than old ones of the same Species. :) '" 3. When animals, after breathing nitrous oxide, are removed from it before compleat exhaustion has taken place, they are capable of being restored to health under the action of atmospheric air.
" 4. Po
• 4. Peculiar changes are effected in the organs of animals by the respiration of nitrous oxide. In animals destroyed by it, the arterial blood is purple red, the lungs are covered with purple spors, both the hollow and compact muscles are apparently very inirritable, and the brain is dark colored.
- 5. Animals are destroyed by the respiration of mixtures of nie trous oxide and hydrogene nearly in the same time as by pure nitrous oxide; they are capable of living for a great length of time in nitrous oxide mingled with very minute quantities of oxygene or common air.” P. 361. · The fourth Research contains the account of various cases of persons, who, having respired the nitrous oxide, were affected with very singular symptoms. In the perusal of those cases, the reader may be either amused or astonished, according as he gives partial or entire credit to the narrations.
This work contains a single plate, with a delineation of a well-contrived mercurial air-holder,
ART. 18. St. Ame's Hill, e Poen. Dedicated to the Hon. Charles
James Fox. 4to. 34 pp. 55. Debrett. 1800. This Poem, which, though by the help of an Introduction and Notes, it is eked out to a 55. book, consists of less than 200 lines, is written in the form of a dialogue between the Poet and his Muse. The former, as is usual on such occasions, expresses an amiable diffi. dence and reluctance to fing, it being winter, and his fancy chilled by the weather, although the 24th of January is Mr. Fox's birth-day. But the Muse (more fuo) is peremptory; and, without further content, the Poet proceeds to celebrate his patron for many personal accomplishments and good qualities which he does possess, and some political merits which, in our opinion, are much more questionable. The poetry, in general, rises not above mediocrity, and sometimes salle below it: but the following elegant lines, by General Fitzpatrick, are introduced.
“ The star whose radiant beams adorn