126 THE BIOLOGY OF DAILY LIFE. 



complete. For chemical photography is now being em- 

 ployed to map the whole heavens, and those wondrous 

 eyes, supplied by chemical science, can behold things 

 invisible to mortal sight. Even darkness is no darkness 

 to them, and neither light nor heat is needed by the 

 actinographic power, which faithfully records rays 

 which have no correspondence with any of our senses. 



What promise has not been kept, what prophecy 

 has not been more than fulfilled? One promise, 

 one prophecy, but that one the most practically im- 

 portant to mankind of all, for " all the labour of a 

 man is for his mouth, and yet the appetite is not filled/'* 



Where is the food supply that was to make famine 

 next to impossible ? There is no lack of material 

 we have sawdust and vitriol in abundance, to fill all 

 things living, at least all humanity. And starving 

 men and women and children are not squeamish, and 

 would eat a substance bearing no remote analogy to 

 bread, and " both wholesome and digestible, as well as 

 highly nutritive." And chemistry in all matters, which 

 require only the rearrangement of molecules, has so far 

 surpassed all expectation that not out of sawdust, but 

 almost any dust, containing the chemical constituents 

 of organic bodies, it would have found out many ways 

 of manufacturing food.t Can we explain this ? Most 

 assuredly we can. The expectation was utterly un- 



* The so-called " Chemical food" is simply a mixture (not in 

 chemical combination) of the following drugs ; Phosphate of 

 lime, phosphate of iron, phosphates of soda and potassa, besides 

 free phosphoric and hydrochloric acids. (See Macnamara's 

 Neligan's Medednes, p. 777). 



f The student will find the following quotation very interest- 

 ing : " We have also learnt, that owing to this identity of com- 

 position, many animals are saved the labour of forming these 



