53 Ro>/al Societi/. 



which ramify on the surface of the heart, those which have hitherto 

 been delineated in the works of anatomists, are few in number com- 

 pared to those which are distributed throughout the muscular struc- 

 ture of the organ, many of which are wholly independent of the 

 blood-vessels. 



" This anatomical demonstration of the ganglia and nerves of the 

 muscular structure of the heart, completely subverts the opinion 

 still entertained by some physiologists, that the sensitive and con- 

 tractile powers of the heart are independent of nervous influence. 

 It further indicates the real source of the action of the heart as an 

 entire organ, from the commencement to the termination of life ; 

 how the circulation of the blood is carried on when the foetus has 

 neither bi-ain nor spinal cord, and how the detached parts of the 

 heart continue to contract for a time in some animals after its total 

 sepai'ation from the body. 



" These dissections are now open to examination by any gen- 

 tleman who may feel interested in the anatomy and physiology of 

 the heart. 



" When Mr. West's drawings of the nerves displayed in these 

 dissections have been completed, they will be presented to the Royal 

 Society, with a description of the appearances delineated." 



2. " On the Influence of the Moon on the magnetic direction at 

 Toronto, St. Helena, and Hobarton." By Colonel Edward Sabine, 

 R.A., V.P. and Treas. 



Having noticed the inference drawn by M. Kreil from the mag- 

 netic observations at Milan and Prague, that the moon exercises an 

 influence on the magnetic direction at the surface of our globe, cog- 

 nisable by a variation in the declination depending on the moon's 

 hour-angle and completing its period in a lunar day, the author pro- 

 ceeds in this paper to state the results of an examination, analogous 

 to that pursued by M. Kreil, into the influence of the moon on the 

 magnetic declination at the three stations of Toronto, St. Helena, 

 and Hobarton. 



The observations employed in this investigation consisted of six 

 years of hourly observation at Toronto, five years at St. Helena, and 

 five years at Hobarton, forming, exclusive of observations omitted 

 on account of excessive disturbance, a total of 105,747 observations. 



The processes are related by which, after the separation of the 

 disturbances of largest amount, the observations were treated, 

 for the purpose of eliminating the variations due to solar influence, 

 and of re-arrangement in a form Idv whicli the inequality of the moon's 

 action at the difl^erent hours of each lunar day might be brought 

 distinctly into view. The results are shown in tables exhibiting the 

 amount of inequality at each of tlie three stations corresponding to 

 each of the twenty-four lunar hours. 



It appears from these results that tlie existence of a lunar diurnal 

 variation in the magnetic declination is shown at each of the three 

 stations of Toronto, St. Helena, and Hobarton, and that it has the 

 same general character at each, viz. that of a double progression in 



