473 



any of these faculties. Neither is it concerned in digestion or assi- 

 milation, nor does its size present any relation with the heart, the 

 lungs, the muscles, the limbs, the vertebrse, the ribs, or any other 

 organ, not even those of reproduction. As, however, its nervous 

 connexions are principally with those parts which are exclusively 

 subservient to the will, it is probable that it is concerned in the 

 completion, and not in the commencement of the voluntary act. It 

 is probable, also, that the principal crossing of impulses from one 

 side to the other takes place in the medulla oblongata and the motor 

 tracts of the brain. Some of the arrangements of its lobules may 

 have reference to the paces and attitudes of different animals. The 

 will, acting through the cerebral convolutions, sets in action certain 

 muscles placed in proper directions ; but the influence of the cere- 

 bellum is required for giving them steadiness amidst the alterna- 

 tions from one set to another, and especially when a slight change 

 disturbs the centre of gravity, and until the balance is effectually 

 restored by a subsequent act of the will operating on antagonist or 

 other muscles. The cerebellum also constitutes an additional focus 

 of nervous influence, and may, therefore, cooperate with the brain 

 in increasing the vital powers, and imparting greater energy to the 

 various functions of the body. 



The author regards the corpus striatum as being a centre for con^ 

 veying to the mind the perception of the motions of the limbs and 

 of their different parts. He concludes with some remarks on the 

 double crossings of the tracts of the centres of the nerves of the 

 arms and legs, and the explanation given by these facts to various 

 pathological phenomena. 



7. " Nouveaux faits aajouter a la Theorie de la Chaleur et a celle 

 de I'Evaporation." Par Daniel Parat, Medecin a Grenoble. Commu- 

 nicated by the President. 



The author commences by explaining his conception of the nature 

 of heat, of which he gives the following definition : — " Mouvemens 

 centraux obsculaires de la cohesion devenus extemporanement plus 

 rapides, et dilatant de plus en plus tous les corps par une augmenta- 

 tion ainsi acquise de toutes les forces centrifuges." He adopts the 

 theory that the evaporation of water in contact with air is a process 

 identical with chemical solution, and adduces as evidence supporting 

 his views various circumstances which are common both to evapora- 

 tion and to the solution of a salt in water. 



8. " On the nature and properties of Iodide of Potassium, and its 

 general applicability to the cure of Chronic Diseases." By James 

 Heygate, M.D., F.R.S. 



The author has been led by his experience to estimate highly the 

 medicinal properties of the iodide of potassium (which he prefers to 

 the tincture of iodine) in various diseases, and thinks that when it 

 is administered judiciously no deleterious effects are likely to arise 

 from its use. 



9. " Observations on the relation which exists between the Re- 



b2 



