A N S W E B S 



TO THE PRACTICAL QUESTIONS, 



AND SOLUTIONS OF THE PROBLEMS, 



m THE 



FOURTEEN WEEKS COUKSE 



IN 



CHEMISTRY, 



f The bold-faced figures refer to the page of the Chemistry; the others to 

 th* number of the Practical Questions."] 



1. Is it likely that all the elements have been discovered? 



It is not, since several have been found lately by means of 

 spectrum analysis. The ancients held that there are but four 

 elements earth, water, air, and fire ; the first representing 

 the solid form of matter, the second the liquid, the third the 

 gaseous, and the fourth the force which changes matter from 

 one form to another. Few of the sixty-five elements are com- 

 mon. Those italicised, in the table on page 14, are rare. 

 The remarkable phenomena of allotropism would seem to in- 

 dicate that, perhaps, what we now consider distinct elements 

 nay be only allotropic states of the same element. Indeed, 

 it is possible to conceive that all substances. are only allotropic 

 forms of one universal essence. In the present state of 

 chemistry this view cannot be proved, and is only a specula- 

 t'on as to what may be discovered in the future. 



2. What is the origin of the term "gas?" 



This word was first used in the iyth century. Explosion^, 

 strange noises, and lurid flames had been seen in mines, caves, 

 &c, The alchemists, whose earthen vessels often exploded 



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