163 



The process referred to for separating these several ingredients 

 from each other yielded, in fact, a pure metallic button, not malleable, 

 but uniting readily with all the other metals that have been tried, 

 except mercury, and whose specific gravity appeared not less than 1 1 . 

 This is the rhodium, which is here announced for the first tune. 



The palladium was precipitated from the alcohol employed for 

 washing the salt of rhodium : it was yielded, indeed, in a very small 

 proportion, but in sufficient quantity, however, to prove that it is 

 actually a simple metal residing in platina, and to induce a suspicion 

 of some error in Mr. Chenevix's investigation, who thought it a 

 compound of platina and mercury ; but our author candidly adds, 

 that he has made several attempts to imitate the synthetical experi- 

 ments of that chemist by solution and amalgamation, but without 

 success. 



The Croonian Lecture on Muscular Motion. By Anthony Carlisle, 

 Esq. F.R.S. Read November 8, 1804. [Phil. Trans. 1805,^. 1.] 



Admitting that there are subjects in the economy of nature which 

 will ever elude our most attentive observation, and that many insti- 

 tutions similar to our Croonian Lecture will probably never attain 

 the end for which they were founded, it cannot, however, be denied 

 that several of them, and ours in particular, have at different times 

 brought forward various collateral, and some of them not unimpor- 

 tant facts, which have in some measure contributed to extend our 

 knowledge of nature. This latter is the point of view in which the 

 present communication is to be considered ; concerning which the 

 author says, that, waving the investigation of the general theory of 

 muscular motion, he shall limit his present inquiry to certain circum- 

 stances which are connected with this motion, considered as causes, 

 or rather as a series of events, all of which contribute more or less 

 as essential requisites to the phenomena. The changes which obtain 

 in muscles during their contractions or relaxations, and their corre- 

 sponding connexions with the vascular, respiratory, and nervous sy- 

 stems, are, he declares, the chief objects of his present investigation. 



The lecture is divided into six sections, of which the following are 

 the heads, together with some of the most prominent facts contained 

 under each of them ; the nature of the performance, which consists 

 chiefly of insulated facts, and our limits in point of time, precluding 

 us from being so minute in our analysis as the importance of the 

 subject may be thought to require. 



Sect. 1. Of the physical and sensible properties of muscles, con- 

 sidered as distinct parts of an animal, and as peculiar organs. In de- 

 scribing the fasciculated texture of the fibres which compose a muscle, 

 and the elasticity of these fibres during the contracted state of the 

 muscle, the author advances an opinion, that this elasticity appears 

 to belong to the enveloping reticular or cellular membrane, and that 

 it may be safely assumed that the intrinsic matter of muscle is not 

 elastic. 



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