1871.] Researches on the Hydrocarbons of the Series C„H2»+2. 487 



of the diaphragm was noticed ; and the varying condition of that muscle, 

 and of the lungs and pleura, with their mutual relations, are com- 

 mented on. 



The importance of this passive tension of the diaphragm is indicated, 

 and exemplified both physiologically and pathologically. It is essential 

 in retaining the supplemental air within the lungs, in restoring the equili- 

 brium of repose, in economizing active muscular power, and in maintaining 

 the pericardial space, &c. 



The action of the diaphragm in relation to the walls of the chest and to 

 other muscles is next discussed ; and the influence of the diaphragm in 

 drawing in the chest-walls, under certain circumstances, is pointed out, and 

 illustrated by cas.;s of injury to the spinal cord. 



The action of ,he intercostal muscles, as necessary adjuncts to the dia- 

 phragm and as muscles of inspiration, is insisted on and illustrated by 

 diagrams ; and a summary of their action is given. 



The agency of the serratus magnus is then discussed ; and reasons are 

 advanced, supported by observation and experiment, to show that it is only 

 under special conditions and to a limited extent that it can be regarded as 

 taking any part in the act of inspiration. 



The mobility of the different costal regions and of the sternum is 

 exemplified by observation and experiment. 



Lastly, the question of abdominal and thoracic breathing, severally in 

 the male and female, is considered ; and reasons are adduced for concluding 

 that the received opinions on this subject are erroneous. 



III. " Researches on the Hydrocarbons of the Series C n B. 2n+2 ." — VII. 

 By C. Schorlemmer. Communicated by Prof. Stokes, Sec.R.S. 



In a former communication*, I have shown that the paraffins, the con- 

 stitution of which is known, may be arranged in four groups. The first 

 group, which I called normal paraffins, contain the carbon atoms linked 

 together in a single chain. Of these I have obtained some new ones, which 

 I shall describe more fully in a further communication. The normal 

 paraffins which I have so far studied are given, together with their boiling- 

 points, in the* following Table : — 



Received April 27, 1871. 



From petroleum. 

 37°- 39° 



From the acids of the 

 series C, l H2 /i _20 4 . 



So-called al- 

 cohol radicals. 



C,H : 



12 



C.H. 

 C,H 



14 



69°- 70° 

 98°- 99° 



69°'5 

 100°-5 



From mannite. 



16 



C 8 H : 



18 



123°-124° 



123°-124° 



Dibutyl. 

 123°-124° 



From methyl- 

 hexyl carbinol. 

 * 124° 



* Proc. Roy. Soc. vol. xvi. p. 367. 



