148 TENTH ANNUAL REPORT OF 



pliorus are wrought into tlie tegetable tissues. The vast bodies of 

 bituminous and anthracite coal occurring in different parts of the 

 earth, were once floating in the atmosphere in the form of carbonic 

 acid and water, and it is only by passing through the organisms of 

 plants that they have been brought to their present state. The food 

 of animals has all been, in like manner, deoxydized. Indeed the 

 leaf of the plant may be regarded as an apparatus specially designed 

 for the application of the solar beam to the reduction of carbon, hy- 

 drogen, sulphur, &c., from the state of oxides. It is only the rays 

 of the sun that can effect this, and the rays of the sun are capable of 

 effecting it only in the leaf of the plant. Hence the interposition of 

 the vegetable between the mineral and the animal kingdoms. Even 

 where'man would effect the reduction of any of the metals from their 

 ores, he is obliged to resort to some substance which has been deoxy- 

 dized by the solar beam in the leaf of the plant. 



All deoxydized bodies, therefore, whatever their immediate origin,, 

 are representations of sun power. Sun power has actually been ex- 

 erted, either directly or indirectly, in their production. And when 

 they revert to the state of oxides, there is an evolution of force equal 

 in amount to that which was expended in their isolation . Hence the 

 real source of steam-power, of electro-magnetic power, and of animal 

 motive power. All of those in the last analysis resolve themselves 

 into sun power, directed through the mechanism of the vegetable cell 

 to the re-solution of oxides. 



We have thus far contemplated oxygen as a dissolving agent. We 

 have seen that it literally goes about seeking what it may destroy. 

 Although respecting the living, and passing by them unharm.ed, it 

 everywhere attacks the organic forms from which life has departed 

 and quickly resolves them into the elements from which they were 

 formed. 



But oxygen is not simply a destroying agent. It takes to pieces 

 the bodies of the dead only' that it may find materials for repairing 

 and building up those of the living. The hydrogen and the carbon 

 which it gathers from the decaying wood or the mouldering dust,_it 

 conveys into the leaf of the growing plant. Having there deposited its 

 burden, it issues again and recommences its wanderings in search of 

 & new one to have a like destination. Could we see oxygen, could we 

 make it visible not only to the mind's eye, but to the eye of sense, as 

 it speeds on its beneficent mission, we might then observe two little 

 winged atoms floating along upon the buoyant air, until at length 

 lighting upon some decaying matter, they lay hold of an atom of car- 

 bon, and taking it up as the two shining ones on the farther side of the 

 river took up Bunyan's pilgrim, bear it away, not to the golden city, 

 but up among the green leaves and beautiful flowers, there to minis- 

 ter to and have part in their verdure and beauty. In observing this, 

 we should recognise oxygen in its most characteristic and habitual 

 office of carrier between the dead and the living. Indeed, at every 

 point of that great cycle through which life and death move hand in 

 hand, the activity of this element is most conspicuous. While by an 

 irreversible law, inscrutable as it is irreversible, life in our world 



