294 ^^ RESPIRATION, 



another, having first passed the buckle and strop (which is at 

 the end of the brace behind the right shoulder) through 

 the ring at the end of the rope, puts the strap through the 

 ring behind the left shoulder, jvnd buckles it to the size of 

 the wearer. This person keeps fast hold of the reel, while 

 the wearer plunges into the water; and the facility with 

 which the rope runs off the reel prevents its being any impe- 

 diment either in swiiximing or diving. 



When it is required to pull the person wearing it to the 

 shore, it is not to be done by winding the rope on the reel, 

 but by shortening the rope by passing one hand over the 

 other as quick as possible. This will pull the wearer on his 

 back, and from the elevated position of the person pulUng, 

 whether he is oo shore or in a boat, the wearer's head and 

 shoulders will be pulled out of the water, and the immer- 

 sion of his head either from debility, his efforts, or any 

 weight he may have hold of prevented. 



The cost of this is eight shillings and sixpence. 



IX. 



On Respiration. By William Allen, Esq. F. R. S. and 

 William Hasledine Pepys, Esq. F. R. S.* 



Nitrogen 'l^NE of the most prominent features in our last comrau- 



evolved when nicationf was the evolution of a considerable quantity of 

 oxigen gas re- . • i j i 



spired. azote, when oxigen gas nearly pure was respired ; and al- 



though a considerable part of this azote must undoubtedly 

 be attributed to the residual gas in the lungs, after the 

 most forcible attempt at expiration, yet the fact seemed to 

 demand still farther investigation, it appearing of conse- 

 quence to ascertain, whether the increase of azote was uni- 

 form throughout the latter s^tagefe of the experiment, or 

 sokl]/ confined to the earlier periods. 

 Large propor- By adverting to our former paper, it will be found, that 



• Philos. Trans, for 1809, p. 404. 

 t See Journal, vol. XXII, p 180. 



in 



