COMMON ALMOND.

'tlier.

1107

u' 1 a suit of^fent

? r ?at.

<>f vitriol gives it a fine crimson-red colour. The presence of hydrocyanic■otter almonds may be readily detected by the usual tests, especially by potashsalt of iron (see p. 240). The quantity oi' this acid is differently stated by dif-a uthorities, and is, probably, not uniform. Schrader (quoted by Dr. Christison,but (; ° n P°‘ sons ) got, from an old sample, 8-5 per cent., and from a new sample, 10'75;Hic^n obtained, from another specimen, so much as 14'33 per cent. Water inthe not i * 13S been was bed (fives evidence of the presence of hydrocyanic acid byAcr- aS ' ant ^ * ron test before referred to.

liep[ f^ a ^ ne matter is frequently deposited by oil of bitter almonds, when it has beenfit c jljt° r some time. Exposure to the air, by which the oil is enabled to absorb oxygen,Ba],] ates > if, indeed, it do not always cause, the deposition. In 1822, Grischow andffep lani1 ( Berl. Jahrb. d. Pharm. 1822, p. 158), and, in 1823, Stange ( Buchner'sat ImIuti" ' 329 ; xvi. 82) declared the crystals to be those of benzoic acid (describedde ’ a s t a tement which was confirmed, in 1830, by Robiquet and Boutron {Ann.differ;*” 1- et * Pbys. xliv. 364). I have met with three kinds of crystalline deposit,f 4cterj ,1 ^j eSseu *i a iiy from each other, and from benzoic acid. 1st. One of these is cha-Iti a j. 8c “ by the emerald-green colour which it produces when dropped into oil of vitriol.Solublg^ m ’ n . utes ) however, the green changes to red. This deposit is orange-yellow,cool 1,1 boiling water, alcohol, and ether: when the alcoholic or etherial solutionsacid) * Ula ® r °us white, light, pearly crystalline plates (resembling crystallized boracicIt ap„ re ** e P“sited. If these crystals be boiled in caustic potash, ammonia is evolved.

9leM to be an amide; but it does not precisely agree either with benzamide orcherry 1 j^ibenzamide). —2nd. A second crystalline deposit is characterized by thecvol V j n ” e “ colour which it assumes when dropped into oil of vitriol, and by its not°H of „®. an »nonia when boiled with caustic potash. Its appearance resembles solidHatic cr' Se ^hen dissolved in boiling alcohol and re-crystallized, it yields silky pris-°f somewhat similar to those of nitrates of ammonia.—3rd. The third* kind

of it |) Slt I did not receive until after it had been digested in alcohol. A short noticeoittall aS - ' Jeen given by Mr. Letheby ( .Lond. Med. Gaz. xxvi. 67). The crystals are° r < a T' W- ail( l lemon-yellow; they dissolve in oil of vitriol, forming a yellow orthey p u c °f°«re(i solution. They are insoluble in water and alcohol. When heatedOtnrno? 6 ' but, unlike the two preceding deposits, do not sublime. They do not evolvej' a ”'ben heated with a solution of caustic potash.

Ilay"b^'Iling the oil of bitter almonds with caustic potash and a ferruginous salt, itffr. of j^P'lved of hydrocyanic acid. It is then a limpid, colourless oil, having a sp.»il. J ,' 13 . and whose odour and taste are scarcely different to those of the ordinarypr °pert - qUet fou nd it innocuous, but Vogel declared that it still retained its poisonousd“e rectfr’,, so >ne earlier experiments which I made on this subject, I found® c itl in • le< I °il highly poisonous, though I could not detect an atom ol hydrocyanicl,| e ac j. V .After the sample had been kept a few months, however, I readily detectedc >pl el ! n 11 by the potash and iron test. By a second and third rectification I havel?jve„ y deprived it of all traces of the acid ; and I then found that four drops of it,°>1: tl)“ a sma U rabbit, had no more effect than the same quantity of any other volatile' n ed. q,! 3 ’ l be animal appeared dull for a few minutes, and the respiration was quick-a »der„o 6 rec t'bcd oil is composed of C 1 * H® O 3 . Now, certain changes which it“'iZoic es - are best explained by assuming that this oil is a compound of the base of° f ben zU / Cla an( I hydrogen. To this base, whose composition is CD* H® 02, the name

I'to

'Xiu, , e or benzoyl has been given ; so that the oil is the hydruret of benzule, and itsand ol,;.__ •*:___ r-H__ .

• and ultimate composition are as follow :—

jS-ule

Jdroge

Composition.

Ultimate Composition.

Atoms. Eq. Wt.

Atoms.

_ 14 ..

Eq. Wt.

84

Per cent.

79 24

Hydrogen

. 6 ....

566

Oxygen...

. 2 ...

.. 16 ...

.. 15 10

nzule L .... 106

1 ...

.. 106 ....

.. 10000

^^'|'ple. 5anip ^ e * oP l b' s > as well as of the first kind of deposit, I am indebted to Mr.