239 



netism, and meteorological instruments, and to which Mr. Brooke 

 had contributed not a little, induced him to consider the practicability 

 of contriving apparatus to render the force-magnetometers self-cor- 

 recting. At present, as the temperature of the magnet varies, a 

 correction is required which is sometimes considerable, and therefore 

 the records of magnetic indication, and of the temperature of the 

 magnet, should be simultaneous to afford proper data for accurate 

 reductions. By this method the labour of deducing results from the 

 photographs is very considerable, and it occurred to Mr. Brooke that 

 an efficient automatic compensation might be applied to the magnet, 

 in the same way as the compensation of the balance of a chronometer. 

 To carry out the necessary experiments a grant was made, and a 

 paper with drawings and descriptions of the ap])aratus constructed 

 was presented to the Society. The apparatus itself was deposited 

 in the Great Exhibition, as offering satisfactory evidence of the 

 advanced state of magnetic science in this country. Recently three 

 sets of instruments have been made ; one set has been sent to 

 Washington, another set is in preparation for the Ecole des Arts et des 

 Metiers at Paris, and a third set for the Cabinet de Physique at 

 Florence. 



Mr. Miller's interesting researches on the rain-fall in the lake 

 districts have been completed, and the results communicated to the 

 Society. 



A small grant was made to Dr. Thurnam for the drawings of 

 crania exhumed from tumuli, as a basis for certain ethnological in- 

 quiries. The drawings have been nearly completed, and Dr. Thurnam 

 hopes in the course of a few months to give so much time to the 

 subject as will be sufficient for the proper arrangement of the 

 drawings, and for describing the evidence on which their appropria- 

 tion depends. 



In the disposal of the Government Grant chemistry has not been 

 forgotten ; grants have been m.ade to the two distinguished chemical 

 philosophers, Dr. Stenhouse and Dr. Hofmann. You are no doubt 

 aware that Dr. Stenhouse has been engaged for a number of years in 

 an extensive series of researches into the chemical relations subsist- 

 ing among the various genera of plants ; the chief aim of these in- 

 quiries has been the illustration of Botany by means of chemical 

 science. Some of these inquiries have already appeared in your 

 Transactions. The grant has been made to assist in defraying the 

 very heavy expenses v/hich are unavoidable, consisting of the cost of 

 materials, and the salaries paid to qualified assistants. 



Dr. Hofmann, in two papers published in your Transactions, has 

 endeavoured to establish a general theory of the constitution of the 

 organic bases, by developing the nature of the relation in which 

 these substances stand to ammonia, and the hypothetical compound 

 ammonium. He has pursued these inquiries very much farther ; 

 and recent experiments have shown that his former views were 

 correct, the facts discovered perfectly harmonizing with theory. 

 There remain still two lines of inquiry, the constitution of some of 

 the fixed crystalline bases, and that of the alkaloids. The alka- 



