UNSOLVED PROBLEMS OF 

 CHEMISTRY 1 



BY TEA EEMSEN, PH. D. 



President of Johns Hopkins University 



THE first duty of the chemist is to examine every kind of 

 matter accessible to him and to determine whether it is an 

 element or not. If it is not, and this is usually the case 

 as regards the things found in nature, his next duty is to 

 attack the compound in every way that is likely to lead to 

 its decomposition, and when he reaches a substance from 

 which he cannot get simpler ones, he calls this an element. 

 Thus iron, copper, gold, silver, tin, hydrogen, and oxygen 

 are elements. None of these can be decomposed by the 

 means at present at the command of the chemist. They 

 are like the letters of a language in some respects. Words 

 can be decomposed or resolved into letters, but letters are 

 the elements of language. What elements are in the 

 earth, in the air, in water? An immense amount of work 

 has been done that has had for its object the answering of 

 this question. The earth has been ransacked almost from 

 pole to pole. The air from all sorts of localities has been 

 examined. The waters, from ocean, rivers, and springs, 

 have been made to stand and answer the searching ques- 

 tions of the chemist ; and animals and plants have been 

 compelled to give up their secrets or some of them. 



What is the result? In brief, it is this: Although we 

 find an infinite number of kinds of matter, all of these can 

 be resolved into a comparatively small number of elements. 

 Indeed, not more than a dozen of these elements enter into 

 the composition of the things that are at all common. But 

 by going into out-of-the-way corners rare things have been 



Published in NcClure's Magazine, February, 1901. 

 20 805 



