CHAP. CV. 



CORYLA'CE^E. QUE'RCUS. 



1931 



1823 



infusion, made with 2 drachms of bruised galls to 12 ounces of boiling water, 

 may be used as an injection ; and, in conjunction with a small portion of spirits 

 of wine, forms a good gargle for relaxation of the uvula." (Stephenson and 

 ChurchUCs Medical Botany, vol. iv. pi. 

 152.) M. Robiquet (as quoted in the 

 Athencciim for April 15. 1837) has been 

 making various experiments on the tan- 

 nin and gallic acid contained in gall 

 nuts. One of the most remarkable re- 

 sults obtained by him is, a knowledge 

 of the great difference of time which it 

 takes to transform pure tannin into 

 gallic acid, and to produce it from the 

 entire nut. Eight months will not com- 

 plete the former operation, while one 

 month is sufficient for the latter ; a 

 proof that the gall nut contains princi- 

 ples, perhaps gum or rather mucilage, 

 which facilitate fermentation. Another 

 important result is a confirmation of the opinion of M. Polongcr, that gallic 

 acid is to be derived from tannin. 



The Dead Sea Apple. Olivier informs us that Quercus infectoria also pro- 

 duces another sort of 

 gall (fig. 1823. from 

 copy furnished us by 

 Mr. Westwood ; and 

 fig. 1824. from the fi- 

 gure given by Oliver, 

 1. 1 5.), of a much larger 

 size than the common 

 gall nut, of a spongy 

 substance, very light, 

 of a brownish red 



colour, covered with \18K BP / ^ ^\ 



a resinous coat, and Illl Wl /^T "* 



furnished with a cir- 

 cular row of tuber- 

 cles, placed round 

 the centre. Olivier 

 does not, however, 

 appear to have been 

 aware of the identity 

 of these galls with the 

 far-famed apples of 

 the Dead Sea, the 

 nature of which has 

 so greatly perplexed 

 naturalists,and which 

 are mentioned, both 

 by Tacitus and Jose- 

 phus, as being beauti- 

 ful to the eye, but crumbling at the touch to dust and bitter ashes. By some 

 writers, the existence of these vegetable productions has been entirely doubted. 

 Pococke supposes them to be pomegranates left for two or three years upon 

 the tree; Hasselquist pronounced these " Poma sodomitica," as they have 

 been called, to be the fruit of the Solanum Me/ongena (the egg plant, or mad 

 apple) ; Seetzen considered them to be the fruit of a species of cotton tree ; 

 Chateaubriand the fruit of a shrub ; and Captains Mangles and Irby have no 

 doubt that they have discovered them in the oskar plant. Mr. Conder, how- 



