PRUSSIC ACID.

(_For the Mirror_.)

The circumstance of Montgomery's recent suicide in Newgate, has led me

to send you the following remarks upon the nature and properties of that

most violent poison, Prussic acid, with which the unfortunate man

terminated his existence.

Were we to consider the constituent parts and properties of the most

common things we are in the habit of daily using, and their poisonous

and destructive natures, we should recoil at the deadly potion, and

shrink from the loathsome draught we are about to take. That which we

consider the most delicious and exhilarating portion of our common

beverage, porter, contains carbonic acid gas, commonly known by the

"spirit," and which the poor miners dread with the utmost horror, like

the Arabian does the destructive blast of the simoon. Oxalic acid, so

much the fear of those accustomed to the medicine--Epsom salts, is made

from that useful article, _sugar_, by uniting with it a smaller portion,

more than it has naturally, of oxygen gas. The air we breathe contains a

most deadly poison, called by chemists azotic gas, which, by its being

mixed with what is called vital air, (oxygen gas,) becomes necessary to

our existence, as much as the one (vital air or oxygen gas) would be

prejudicial without the other; and _Prussic acid_, the most violent of

all poisons, is contained in the common bitter-almond. But these most

destructive substances are always found combined with others, which

render them often perfectly harmless, and can be separated only by the

skill of the chemist.

The Prussic acid (by some called hydrocyanic acid) is a liquid,

extracted from vegetables, and contains one part of cyanogen and one

part of hydrogen. It is extracted from the bitter-almond, (as has been

stated,) peach-blossom, and the leaves of the laurocerasus. It may also

be obtained from animal substances, although a vegetable acid. If lime

be added to water, distilled from these substances, a Prussiate of lime

is formed; when, if an acid solution of iron be added to this mixture,

common Prussian blue (or Prussiate of iron) is precipitated. The acid

may be obtained from Prussiate of potash, by making a strong solution of

this salt, and then adding as much tartaric acid as will precipitate the

potash, when the acid will be left in solution, which must be decanted

and distilled.

Its properties are a pungent odour, very much resembling that of

bitter-almonds, with a hot but sweetish taste, and extremely volatile.

It contains azote, with which no other vegetable acid is combined; it is

largely used in the manufacture of Prussian blue. It is the most violent

of all poisons, and destroys animals by being applied to the skin only.

It is stated by an able chemist, that a single drop applied to the

tongue of a mastiff dog caused death so instantaneously, that it

appeared to have been destroyed by lightning. One drop to the human

frame destroys life in two minutes.

But when chemically combined with other substances, its power is in a

great measure neutralized, and it becomes a valuable article, both to

the chemist as a test, and to the physician as a medicine. The Prussiate

of potash and iron will enable the chemist to discover nearly the whole

of the metals when in solution, by the colours its combination produces.

Dr. Zollekoffer says, that in intermittent fevers the Prussiate of iron

is in its effects superior to Cinchona bark, and says it never disagrees

with the stomach, or creates nausea even in the most irritable state,

while bark is not unfrequently rejected; a patient will recover from the

influence of intermitting and remitting fevers, in the generality of

cases, in much less time than is usual in those cases in which bark is

employed. S.S.T.

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The Mirror of Literature, Amusement, and Instruction. Volume 12, No. 325, August 2, 1828 · 第 15 / 47 题