Intelligence and Miscellaneous Articles. 151 



MARYLEBONE LITERARY AND SCIENTIFIC INSTITUTION. 



This Institution is rapidly advancing to a state of permanent 

 prosperity, and may confidently be expected to become one of the 

 most important and interesting establishments of the kind in the 

 metropolis. The Committee have taken spacious and commanding 

 premises, situate No. 17, Edwards-street, Portman-square, where 

 the business of the Institution is now conducted. A lecture room is 

 to be built in the rear of the premises capable of containing at least 

 600 persons. Until then the handsome and spacious suite of rooms 

 on the first floor, which have been thrown into one for the purpose, 

 will be occupied for the delivery of lectures. 



The audiences are numerous and highly respectable, and the 

 lectures delivered during the last six months have been eminently 

 calculated to command them. Among those who have given in- 

 struction in different branches of science or literature at this Insti- 

 tion are Dr. Lardner, Dr. Ritchie, Dr. Copland, Dr. Southwood 

 Smith, Sir A. Carlisle, Professor Burnett, Messrs. John Taylor, 

 T. Phillipps, Wallis, Brayley, Jun., and Hemming, the latter of 

 whom is President of the Institution. 



The Committee are now forming classes for the instruction of 

 members in chemistry, languages and music. The following list of 

 the officers of the Mar} lebone Literary and Scientific Institution 

 will sufficiently prove the estimation in which it is held, while it is a 

 guarantee for the continuance of its prosperity. 



President: John Hemming, Esq. — Vice-Presidents: E. W. Bray, 

 ley, Esq., F.S.A.; Sir Anthony Carlisle, F.R.S. ; James Copland, 

 M.D., F.R.S. ; Raikes Currie, Esq.; T. H. Holdsworth, Esq., 

 F.G.S. ; Rev. Dr. Lardner, F.R.S., &c. ; Robert M' William, Esq.; 

 Basil Montague, Esq.; Richard Taylor, Esq., F.L.S.; G. Ainslie 

 Young, Esq. — Treasurer: Thomas Bridgman, Esq. 



XXVIII. Intelligence and Miscellaneous Articles. 



TEST FOR HYDROCYANIC OR PRUSSIC ACID, AND METHOD OF 

 APPRECIATING THE QUANTITY. 



WE are informed by Mr. John T. Barry that the nitrate of silver, in 

 common with other salts of that metal, is so extremely delicate 

 a test of the presence of hydrocyanic acid, that its detection is not 

 difficult in a drop of water containing far less than the ten thousandth 

 part of a grain of that poisonous agent. For instance, if one minim 

 of the dilute medicinal solution be mixed with a pint of water, its pre- 

 sence may be demonstrated in a single drop of the mixture. But 

 what is of more consequence is, that although the mixture be con- 

 taminated with various organic substances, such as those contained 

 in articles of diet, milk, coffee, tea, porter, wine and soups, so far as 

 is yet known the test retains its sensibility unimpaired. Mr. Barry, 

 however, thinks that this extreme sensibility, while it renders the 

 evidence of the silver test conclusive as to the absence of prussic 

 acid, will be of more limited service in establishing its presence, for, 



