344 Mr. Beke on the Complexion of the Ancient Egyptians. 



that it contains 8*74 per cent, of water of crystallization. Now 

 the atomic weight of the salt according to my experiments is 

 372, and if the above per centage of water of crystallization 

 be taken as correct, it will be found that 372 parts of the 

 anhydrous salt will combine with 35*62 parts of water, which 

 is very nearly equal to 4 atoms ; this agrees with the state- 

 ment of M. Caillot, who considers the quantity of water in his 

 salt as equal to 4- atoms. The proportions of the constituent 

 salts in 100 parts as given by Caillot, is very nearly the same 

 as that given in my analysis : according to him the propor- 

 tions are as follows : Bicyanide of mercury 68*49 ; bromide 

 of potassium 31*51. M. Caillot says that diluted nitric acid 

 when mixed with the salt decomposes it, forming nitrate of 

 potass and bi-bromide of mercury, and disengaging hydro- 

 cyanic acid ; and certainly, reasoning from the known action of 

 many of the acids upon the iodo-cyanide of potassium and mer- 

 cury, we might a priori have expected this. In my own experi- 

 ments, however, I did not find it to be the case, for when the 

 salt was carefully prepared, so that no uncombined bi-cyanide 

 of mercury was present, the cold, and even concentrated 

 mineral acids did not disengage any hydrocyanic acid, neither 

 did the same acids when hot; a prolonged digestion with or 

 without heat would in all probability effect a decomposition, 

 and it is more than likely that this was done in M. Caillot's 

 investigations. 



I cannot find that the chloro-cyanide of potassium and mer- 

 cury has been described. Being at present engaged in the 

 investigation of the salts formed by the combination of bi- 

 cyanide of mercury with certain haloid salts of the alkaline 

 metals, as well as with the organic alkalies and the chloride 

 and bromide of ammonium, I hope to make them the subject 

 of a future communication. 



R. H. B. 



XL 1 1 1. On the Complexion of the Ancient Egyptians. By 

 Charles T. Beke, Esq., F.S.A* 



HPHE main difficulty which has had to be contended with, 

 •*■ in the consideration hitherto given to the subject of the 

 colour of the ancient Egyptians, is this; — that, whilst the 

 only conclusion which we are warranted in drawing from the 

 descriptions given of that people by the earliest writers of 

 Greece, is, that they were in outward appearance almost si- 



* From the Transactions of the Royal Society of Literature, vol. iii. 

 Part I. ; read before the Society on March 24th, 1836. 



