468 Leclitres. 



coarsely powdereJ, or even in small frajiments, are able 

 . during ihtir passage through the alimentary canal, to pro- 

 duce irritation, erosion, laceration, or anv meclxanical al- 

 , ttranon upon the parts with which they conii- in contact ? 

 He endeavours to reKute the opinion ot^^ those who think 

 that any injury can aii-e from taking fragments of e;liss or 

 vitreous sub>lances into the s omach, and relates a number 

 of experimenir made upon himself bv freq.ienlly swallow- 

 ing sharp pieces of broken glass, both on an empty stomach 

 and after meals. From these ex,jerimei:*s he infers, that 

 glass, and analogous substances, produce no chemical ac- 

 tion on the digestive organs of living animals ; nor are they 

 acted upon by the fluids or gases contained in these organs ; 

 that the mechanic:u effects, said by authors to have been 

 produced by i.rcgiiar fragments of glass on the intestinal 

 tube, f.ave been niercly imagined and never really seen, and 

 that stili less can any such effects arise i'rom glass in pow- 

 der, whether coarse or fine. That experiments purposely 

 made upon living animals prove bevond diAibt, not only 

 that those substances are incapable of mechanicallv injuring 

 the alimentary canal, but that they do not produce the 

 slightest irriiation in it ; and that any one may easilv satisfy 

 himself by trying the experiment, that they do not produce 

 the least uneasy sensation. He concludes, therefore, that 

 it is erroneous to retain in the class of poisons, already too 

 numerous, a particular order of mechanical poisons, acting 

 by irritating and lacerating the organs to which they are ap- 

 plied, since it is proved such an order has no existence in 

 nature. 



LECTURES. 



Thea tre of Aiiato my . 



Lectures on Anatomy, Physiology, Pathology, and Sur- 

 gery, by Mr. J.hn Taunton, F.A.S. Member of the Royal 

 College of Surgeons of London, Surgeon to the City and 

 Finsbnry Dispensaries, City of London Truss Society, &c. 



In this Course of Lectures it is proposed to take a com- 

 prehensive view of the structure and esconomy of the living 

 body, and to consider the causes, symptoms, nature, and 

 treatment of surgical diseases, wiih the mode of performing 

 the diflerent surgical operations ; forming a complete course 

 of anatomical and physiological instruction for the medical 

 or surgical student, the artist, the professional or private 

 gentleman. 



Anarnple field for professional edification will be afforded 

 by th€f opportunity which pupils may have of attending the 



clinical 



