1828.] Proceedings of Philosophical Societies. 387 



Hydrobromic acid gas is very soluble in water : the solution 

 may be prepared, either by treating a solution of sulphuretted 

 hydrogen with brome, or by causing the acid gas disengaged by 

 any of the processes described to pass into water ; the solution 

 becomes hot, increases in volume, acquires great density, and 

 the property of exhaling white vapours when exposed to the 

 air : when properly prepared, this solution is colourless ; but if 

 the hydrobromic acid gas is mixed with vapour of brome, the 

 solution becomes of a deep orange-red colour. It may have 

 this colour imparted to it by shaking the solution with br6me, 

 and it dissolves more of it than equal volumes of water. This 

 solution may be termed bromated hydrobromic acid; if it be 

 heated, vapours of brome and hydrobromic acid are both evolved, 

 and a solution of acid remains which is nearly colourless, but 

 less concentrated. 



Chlorine immediately decomposes solution of hydrobromic 

 acid, and gives it a tint of uncombined brome ; nitric acid acts 

 upon hydrobromic acid less suddenly, but with more energy as 

 soon as re-action has commenced ; much brome is produced, 

 and probably water and nitrous acid ; a fluid is obtained analo- 

 gous to aqua regia, and which dissolves gold and platina. Sul- 

 phuric acid possesses to a certain extent the power of decom- 

 posing hydrobromic acid ; so that it is not uncommon, when 

 this gas is evolved by means of sulphuric acid, to see vapours of 

 brome and sulphurous acid formed by a re-action, the cause of 

 which will be easily understood. 



iTo le continued,) 



Article XIV, 



Proceedings of Philosophical Societies, 



MEDICO-BOTANICAL SOCIETY OF LONDON. 



The First General Meeting of this Society was holden on 

 Friday, the 13th of October, at eight o'clock, p.m. Sir James 

 McGregor, Director General of the Army Medical Board, Presi- 

 dent, in the Chair. 



After the usual business of the Society had been gone 

 through, a letter from his Royal Highness the Duke of Clarence 

 was read, desiring his name to be added as an Honorary Patron, 

 and regretting that his residence at Bushey Park excluded the 

 possibility of his attendance that evening. 



The Director (Mr. Frost) then delivered his Oration, in which 

 he congratulated the Society on the rapid advance it had made 

 during the last Session, and the great benefit it had derived 

 from the unwearied zeal which many of its members exerted in 

 its behalf. He also informed the meeting that their distin- 



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