118 WRITINGS OF JOSEPH HENRY. [1855- 



the organic molecules which deserves particular attention, 

 namely, that it must always be accompanied with the ex- 

 hibition of power or energy, with a disturbance of the cethe- 

 rial equilibrium in the form of heat, sometimes even of light, 

 or perhaps of the chemical force, or of that of the nervous 

 energy, in whatever form of motion the latter may consist. 

 It is a general truth of the highest importance in the study 

 of the phenomena of nature that whenever two atoms enter 

 into more intimate union, heat or some form of motive 

 power, is always generated. It may however be again im- 

 mediately expended in effecting a change in the surround- 

 ing matter, or it may be exhibited in the form of one of 

 the radiant emanations. 



Balance of Nature. — The term balance of organic nature 

 was first applied, we think, by Dumas to express the rela- 

 tions between matter forming animals and vegetables, and 

 the same matter in an inert condition. We shall apply the 

 term "balance of nature" in a more extended sense, and in- 

 clude within it the balance of power, as well as the trans- 

 formations of matter. The amount of matter in the visible 

 universe is supposed to remain the same, though it is subject 

 to various transformations, and appears under various forms, 

 — now built up into organic molecules, and now again resolved 

 into the simple inorganic compounds. The carbon and other 

 materials absorbed from the air by the plant is given back to 

 the atmosphere by the decaying organisms, and thus what 

 may be called a constant balance is preserved. But this 

 balance (if we may so call it) does not alone pertain to the 

 matter, but also to the energ}^ which is employed in produc- 

 ing these changes. It may disappear for a while, or may 

 be locked up in the plant or the animal, but is again des- 

 tined to appear in another form and to exert its effects per- 

 haps in distant parts of celestial space. 



To give precision to our thoughts on this subject let us 

 suppose that all the vegetable and animal matter which now 

 forms a thin pellicle at the surface of the earth were removed 

 — that nothing remamed but the germs of future organisms 

 buried in the soil and ready to be developed when the proper 



