xviii Proceedings. S^MnrcJi 6th, igoo. 



Ordinary Meeting, March 6th, 1900. 

 Horace Lamb, M.A., LL.D., F.R.S., President, in tlie Chair. 



The thanks of the members were voted to the donors of the 

 books upon the table. 



Dr. 1'". H. Bowman brought to the notice of the members 

 the results of a series of experiments recently made in regard to 

 the preservation of milk or cream by aeration. Sterilised air is 

 aspirated through the milk or cream in suitable vessels, and after 

 aeration for about twenty minutes in the sterilised air at ordinary 

 temperature it is found that the milk or cream will keep sweet 

 for from eight to ten days, though absolutely unchanged in 

 composition in any way. The same milk or cream unaerated 

 will become sour in about two or three days. This discovery 

 renders it possible for milk or cream to be kept or distributed in 

 a perfectly pure and natural condition without the aid of any 

 ])reservatives or antiseptics. 



A paper " On the Production of Nitric Acid from Air 

 by means of the Electric Flame," by A. McDougall, B.Sc, 

 and F. Howles, P.Sc, was read by the latter. 



The paper is printed in full in the Memoirs. 



Various pieces of the apparatus used in the experiments were 

 exhibited, photographs of the larger parts being thrown on the 

 lantern screen. A discussion followed the reading of the paper. 



Ordinary Meeting, March 20th, 1900. 

 Horace Lamb, M.A., LL.D., F.R.S., President, in the Chair. 



The thanks of the members were voted to the donors of the 

 books upon the table. 



There being no paper before the meeting, a discussion took 

 place on the principles underlying Michelson's " echelon '' 

 spectroscope, in which a spectrum of a very high order is produced 

 by half-a-dozen fairly thick plates of glass, so placed that their 

 edges form a series of steps. 



