NO T THE EX PL A NA TION OF A FACT. 57 



according to the disposition of its molecular machinery," 

 etc., I venture to think that there are few who would be 

 disposed to argue the question, or to doubt for an instant 

 that I had explained the whole mystery of life in a very few 

 words. But, on the other hand, if I say, " Here is a small 

 piece of soft colourless stuff, into which various substances 

 pass and undergo conversion into similar matter ; and that 

 gradually some of this soft colourless material becomes 

 resolved into new matter differing in composition from the 

 original colourless material, as well as from the surrounding 

 constituents," I state facts in words which a child could 

 understand; but at every step I should be met by the 

 enquiry "why?" or "how?" and numerous simple questions 

 would be proposed which I could not answer. The natural 

 inference might be that I really knew very little about the 

 matter, and this inference would not be very wide of the 

 exact truth. The very points upon which further informa- 

 tion is required can be and ought to be very distinctly 

 stated in language intelligible to all. Nothing can en- 

 courage enquiry more than telling people what we know in 

 the simplest, plainest way possible, and drawing their atten- 

 tion to what we do not know, or to what we cannot explain, 

 and I am sure that all observers who earnestly desire to see 

 knowledge advanced will support me in the view that 

 scientific men should express what they have to say clearly 

 and simply, and not confuse people less learned than them- 

 selves by employing high-sounding words, the meaning of 

 which is at best doubtful and obscure, or ill-defined, and in 

 but too many instances not to be clearly explained by the 

 authorities themselves. 



" Molecular'' Of late few terms have obtained such pre- 



