NATURAL PHILOSOPHY. 187 



deficiency of heat of friction in the plate glass and rubber of the machine, 

 which a perfect determination, and comparison with the amount of work 

 spent in turning the machine, would certainly have detected. 



The application of mechanical principles to the mechanical actions of living 

 creatures was pointed out. It appears certain, from the most careful physio- 

 logical researches, that a living animal has not the power of originating 

 mechanical energy ; and that all the work done by a living animal in the 

 course of its life, and all the heat that has been emitted from it, together with 

 the heat that would be obtained by burning the combustible matter which 

 has been lost from its body during its life, and by burning its body after death, 

 make up together an exact equivalent to the heat that would be obtained by 

 burning as much food as it has used during its life, and an amount of fuel 

 that would generate as much heat as its body if burned immediately after 

 birth. 



On the other hand, the dynamical energy of luminiferous vibrations was 

 referred to as the mechanical power allotted to plants (not mushrooms or 

 funguses, which can grow in the dark, are nourished by organic food like 

 animals, and like animals absorb oxygen and exhale carbonic acid) to enable 

 them to draw carbon from carbonic acid, and hydrogen from water. 



In conclusion, the sources available to man for the production of mechani- 

 cal effect were examined and traced to the sun's heat and the rotation of the 

 earth round its axis. 



Published speculations were referred to, by which it is shown to be pos- 

 sible that the motions of the earth and of the heavenly bodies, and the heat of 

 the sun, may all be due to gravitation; or, that the potential energy of gravita- 

 tion may be in reality the ultimate created antecedent of all motion, heat, and 

 light at present existing in the universe. 



ON THE ROTATORY MOVEMENTS OF THE CELESTIAL BODIES, 

 AND THE SPIRAL FORMS OF NEBTJLJS. 



At a recent meeting of the Astronomical Society. England, Mr. K"asmyth 

 read a paper entitled, " Suggestions respecting the Origin of the Rotatory 

 Movements of the Celestial Bodies, and the Spiral Forms of the Nebula?, as 

 seen hi Lord Rosse's Telescope." What first set me thinking on this sub- 

 ject, was the endeavor to get at a reason why water in a basin acquires a 

 rotatory motion when a portion of it is allowed to escape through a hole in 

 the bottom. Every well trained philosophical judgment is accustomed to 

 observe illustrations of the most sublime phenomena of creation in the most 

 minute and familiar operations of the Creator's laws, one of the most cha- 

 racteristic features of which consists in the absolute and wonderful integrity 

 maintained in their action, whatsoever be the range as to magnitude or dis- 

 tance of the objects on which they operate. For instance, the minute particles 

 of dew which whiten the grass blade in early morn are, in all probability, 

 moulded into spheres by the identical law which gives to the mighty sun its 

 globular form ! Let us pass from the rotation of water in a basin, to the con- 

 sideration of the particles of a nebulous mass just summoned into existence 

 by the fiat of the Creator, the law of gravitation co-existing. The first 



