152 hitelligence and Miscellaneous Articles. 



accordance with the assertions made 1700 years ago by the geo- 

 grapher Claudius Ptolemy of Alexandria, that the sources of the 

 Nile are in the Mountains of the Moon, and that the lakes of that 

 river receive the snows of those mountains. 



According to the latest intelligence received from the Missionaries, 

 Mr. Rebmann had set out on the 5th of April last for Uniamesi and 

 the lake there ; so that we may confidently anticipate the speedy so- 

 lution of the great problem of geography — Nili queer ere caput. 



ON THE ESTIMATION OF THE WEIGHT OF ANTIMONY. 

 BY M. H. ROSE. 



Antimonious acid (oxide of antimony Sb + 30) may be estimated 

 in a mode analogous to arsenious acid, by means of a solution of gold. 

 This method requires, however, more precautions than the determi- 

 nation of arsenious acid. For, at the same time that the gold is re- 

 duced, antimonic acid is separated, which when it has once been pre- 

 cipitated, is very difficultly soluble in hydrochloric acid ; this preci- 

 pitation must therefore be prevented by the previous addition of a 

 great excess of hydrochloric acid. 



Separation of Antimony from Tin. — Tlie author has already pro- 

 posed a method for the separation of these two metals : this consists 

 in eliminating the antimony in the form of antimoniate of soda by 

 means of water, from a solution of tin in hydrate of soda. As, how- 

 ever, antimoniate of soda isnotperfectlyinsoluble in water, this method 

 does not give perfectly accurate results ; a more precise one consists 

 in the separation of antimoniate of soda from stannate of soda by 

 means of dilute alcohol. 



When an alloy of these two metals is to be separated, the first step 

 to be taken, is that of completely oxidizing both by nitric acid. 

 The acids obtained, from which the nitric acid is to be expelled by 

 gently heating them, are to be fused in a silver crucible with hydrate 

 of soda. The fused mass is moistened with water, and then alcohol 

 is to be added ; dilute alcohol is to be used for washing the anti- 

 moniate of soda. 



The alcoholic solution of stannate of soda is exposed to a gentle 

 heat to expel the greater part of the alcohol, then diluted with water, 

 and saturated with dilute sulphuric acid, and lastly the tin is to be 

 precipitated in the state of sulphuret by means of hydrosulphuric 

 acid, and then to be converted into oxide of tin. 



The antimoniate of soda is dissolved in a mixture of hydrochloric 

 and tartaric acids, and the antimony is precipitated from the solution 

 by hydrosulphuric acid gas in the form of sulphuret of antimony. 



Separation of Antimony from Tin and Arsenic. — The metals are 

 oxidized by nitric acid, tiie oxidized mass is evaporated to dryness. 

 and then fused in a silver crucible with hydrate of soda. The fused 

 mass is difi'used in water and treated with dilute alcohol. Antimo- 

 niate of soda remains, which does not dissolve, washed with dilute 

 alcohol, and is afterwards dissolved in a mixture of hydrochloric and 



