Page:Proceedings of the Royal Society of London Vol 1.djvu/183

Rh The process referred to for separating these several ingredients from each other yielded, in fact, a pure metach 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 11. This is the rhodium, which is here announced for the ﬁrst time.

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.

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.