Proceedings of Learned Societies. 303 



water, with, four or five drops of glacial acetic acid, and when 

 sufficiently washed and dried, be appropriately trimmed and 

 mounted for the microscope." 



On the Method of Observing Vaeiable Stars, by George 

 Knott, LL.D. Lond., F.R.A.S., and Joseph Baxendell, F.R.A.S., 

 etc. Printed for private circulation. In a former number we 

 mentioned the formation of a " Variable Star Committee," whose 

 special function is to watch and collect information concerning 

 variable stars ; and we likewise published a short paper by Mr. 

 Knott,* explaining the method to be adopted in these curious and 

 important investigations. The pamphlet now before us conveys 

 more detailed information on the same point. The writers recom- 

 mend the magnitude of stars to be determined according to the 

 plan of the Rev. R. Dawes, by ascertaining the exact amount of 

 aperture at which they cease to be visible, and they supply examples 

 of the mode of comparing one star with another, of estimating the 

 difference between them, and of recording the observations. We 

 presume that this pamphlet may be obtained on application to 

 Mr. Knott, Woodcroft Observatory, Cuckfield, or to Mr. Joseph 

 Baxendell, Manchester ; but we should have thought it better that 

 the Variable Star Committee should have issued it as their official 

 code of directions. There can be no doubt that the observation of 

 variable stars, and an accurate register of their increase and decrease 

 of brilliance, and of the exact time occupied in such changes, is 

 calculated to throw much light upon obscure but very interesting 

 questions of stellar astronomy ; and it is a work in which private 

 students may successfully engage, as it will not require the costly 

 apparatus of a regular observatory, nor make extravagant demands 

 upon their knowledge and skill. It is, however, a kind of labour 

 in which systematic co-operation is of great advantage, and we 

 recommend that all who are disposed to engage in it, should at 

 once put themselves in communication with Mr. Knott and Mr. 

 Baxendell. 



PROCEEDINGS OF LEARNED SOCIETIES. 



BY W. B. TEGETMEIER. 



BRITISH ASSOCDATION FOR THE ADVANCEMENT OF 



SCIENCE. 



At the recent meeting of the British Association several examples 

 were brought forward demonstrating the direct bearing of scientific 

 researches upon the advance of medical science. No sooner is 

 any new substance (whether an elementary body, such as thallium, 

 or a compound) discovered, than experiments are made to investigate 

 its physiological and therapeutical action on the living organisms of 

 men and animals. In many cases these experiments are made by 

 the observers on their own bodies, and the records of science offer 

 * See iNTEiiiECTTJAi, Obseevee, April, 1863, p. 212. 



