504 ESSAYS and OBSERVATIONS 



Art. XX. 



Remarks on the Intercnftal Mufcles^ by Alex- 

 ander Monro, F. R. S. Profcjjor of 

 Anatom) in the Univerfit) of Edinburgh. 



•"IT AUVRY * fhewed the mifappU- 

 -» cation of Mr Bayle's propofed de- 

 monftration of the aflion of the internal 

 jntercoflal mufcles, from his inattention 

 to the ribs not keeping in the fame paral- 

 lelifm when they are raifed, as when they 

 ^re deprefled, becaufe of the greater mo- 

 tion of the lower than of the higher ribs ; 

 and he took notice of the fame demon- 

 ftration, proving equally that the anterior 

 part of thefe internal intercoflals mufb adl 

 in infpiration, as Bayle would have their 

 poflerior part to adl in expiration : But 

 neither he, nor any other writer of my 

 acquaintance, has applied this demonftra- 

 tion of Bayle's, which, granting the pa- 



rallelifm 



* Aoat. raifoDD* part 2. chap. 14. 



