120 SIXTH REPORT — 1836. 



that the process of putrefaction proceeds as rapidly at least before death 

 as it does after it, but that the products of it are carried off before they 

 become offensive to the senses." 



The last absorbent process mentioned is that by which the water in 

 the ventricles of the brain is renewed, lliat this fluid is constantly in 

 a state of renovation is certain from the fresh condition in animals that 

 have been recently killed, and from the smell of substances of a foetid 

 nature being soon perceived in the water of the ventricles of the brain. 

 There are no lymphatics in the brain. It would appear that the inter- 

 nal cavity of the ventricles, or the veins of the arachnoid coat, are sup- 

 plied with imbibers, after the manner of the lungs ; and that it is by 

 these vessels, in connection with the exhalants, that the water of the 

 ventricles is renewed. As there are no surfaces within the cranium 

 from which liquids required for the repair of the system could be taken 

 up, there would be, according to Dr. Carson's views of the uses of the 

 lymphatic system, no employment for it ; and he regards the total abs- 

 ence of these vessels from the brain as confirmatory of those views*. 



On the Gyration of the Heart. By Augustus F, A. Greeves, Fellow 

 of the Royal Colleges of Suregons of Edinburgh and London. 



The following are the propositions which the author endeavoured to 

 establish : 



1. Muscular fibres can act as levers without a solid fulcrum, if there 

 be another set of fibres set at an angle and contracting simultaneously. 



2. A hollow organ may be dilated by the contraction of such an ar- 

 rangement of fibres, if in contracting they become more parallel to a 

 plane passing longitudinally along the axis of the organ. 



3. That there are two spiral, two longitudinal, and one diagonal set 

 of fibres in the heart interlacing each other. 



4. The ventricles gyrate incessantly to and fro upon their axis ; a. In 

 systole or involution, as the left hand pronates ; 6. In diastole or evo- 

 lution, as the left hand supinates. 



5. The double spiral curve of the two great arteries forms a compen- 

 sating and regulating movement, causing, 



6. First, a diminution of friction ; 



7. Second, steadiness and celerity of motion, on the principle of the 

 tilt-hammer ; 



8. Third, an isochronous action, on the principle of the balance-wheel 

 and spring ; 



9. Fourth, the progression of the whole heart. 



10. That the function of the auricle is to maintain the equilibrium of 

 the venous system. 



1 1 . The first sound is produced by the sudden tension and sudden 



* See on this subject Reports of the Association, Vol. IV., Transactions of the Sec- 

 tions, p. 92, 93. 



