Royal Inslitulion. 377 



Mr. Brande proceeded to illustrate the effects and laws of 

 chemical attraction, by an extended series of experiments : he 

 observed^ that a total change in the properties of bodies was the 

 most obvious result of a chemical action ; that insipid, inodorous, 

 and insoluble substances acquired flavour, smell, and solubility; 

 and that the third substance resulting from the union of tv.o 

 bodies, did not possess- the intermediate qualities of its compo- 

 nent parts, but exhibited new and unexpected properties ; that 

 change of form or state was a frequent attendant on chemical 

 action ; that solids became fluids and gases ; fluids were solidified; 

 and aeriform bodies, quitting their elastic state, acquired a liquid 

 or.solid form. These phaenomena were separatel)' illustrated bv 

 experiments. 



Mr. Brande concluded his lecture with an examination of the 

 laws of simple and double decomposition, and with a general 

 view of the theory of definite proportions, in which he demon- 

 strated the tendency of bodies to unite only in certain relative 

 weights; and that, when they combine in more than one pro- 

 portion, the second, third, or fourth quantities are multiples or 

 divisions of the first. Mr. Brande contrasted these views with 

 those advanced by BerthoUet in his " Chemical Statics," and 

 proved the correctness of the former, and the imperfection and 

 iutility of many of the latter. 



In some experiments with carburetted hydrogen, the Professor 

 took oc(fasion to advert to the applications of this gas to oecono- 

 mlcal purposes, which, with few inconveniencies, held out many 

 advantages. The question was too extended and important to 

 be then entered upon ; he therefore merely noticed the quantity 

 of gas afforded by a given quantity of coals, and the proportion 

 required to feed an Argand's lamp. We understood that a chal- 

 dron of Newcastle Wallsend coals afforded 10,000 cubical feet 

 of gas fit for burning ; of v.'hich, between three and four cubical 

 feet were consumed by each Argand's burner per hour. 



This lecture was interspersed with several applications of th? 

 principles laid down, to the pheenomena of art and nature. 



It is obvious, said the Professor, that the effects of chemical 

 combination are referable to simple laws productive of invariable 

 results ; and hence we discern, in the minutest atoms and com^ 

 binations of matter, the same display of unerring harmony which 

 is exhibited upon a great and magnificent scale throughout the 

 system of the universe. 



Mr. Brande in his eleventh lecture dwelt upon the advances 

 which had been made in cl;emistry daring the last century, and 

 observed, that new and powerful instruments of research had 

 been discovered. He tlven proceeded to discuss the relation of 

 the mechanical forms to the chemical constitution of bodies ; 



and. 



