234 KANSAS CITY REVIEW OF SCIENCE. 



of motion of the same kmd of invisible ether. Electricity and heat are surely- 

 very much of the same nature. Is electricity only a mode of motion? Believe 

 it who can. 



I will not be surprised if some things that are erroneous shall be found in 

 this paper. I will be surprised if its main positions are not sooner or later ac- 

 cepted by men of science. Those who are too established, to re-invoice the store- 

 house of their knowledge, will likely remain where they are, at least, till they fol- 

 low the multitude. But there is a spirit abroad in the land that asks even what 

 is called science to show its authority. This spirit was never more active and 

 more earnest than now, and the truth is going to lose nothing when it goes forth 

 in methods of legitimate operation. I respectfully ask that the themes here dis- 

 cussed receive from this class of minds serious consideration. Having held to 

 these views for the last eight years, I have gone with them into different realms 

 of science, and everywhere they have caused me to see with a clearer hght. 

 This is so in astronomy, in geology, in meteorology, and in all that pertains to 

 organic nature. 



After all, it is not so much that need be thrown away. Thermodynamics is 

 indeed a science, and here "the half has never been told." Heat is the source of 

 force. It causes motion. It may be said to accomplish work. Yes, surely, if 

 it be the source of all attraction and of all repulsion. Scientists may measure its 

 force, and if they choose they may reckon it by foot-pounds. To all this we have 

 no objection; we are pleased. And we expect to see a great deal more done in 

 these directions. Go on gentlemen, nor stop till you find a perfect system of 

 applied mathematics running throughout the whole physical world. It is there, 

 whether you will be able to gather it up, or not. But all this makes nothing for 

 the theory that heat is only a mcde of motion. 



SELENIUM AND ITS USES. 



Selenium is an elementary substance that is found in nature associated with 

 deposits of sulphur. It was discovered in 1817 by Berzelius. This somewhat 

 rare element crystallizes in four sided prisms, and is about four times as heavy as 

 water. It is as brittle as glass, but, unlike the latter substance, is readily cut or 

 scratched. Selenium, when suddenly cooled from a fused state, possesses a red- 

 dish-brown, metallic lustre with a conchoidal fracture, which by exposure to the 

 air, assumes a dull, leaden-gray color. The name, selenium, is derived from the 

 Greek word Selene, the moon. When rapidly cooled from a state of fusion, 

 selenium is a non-conductor of electricity, but when cooled very slowly it is a 

 conductor. In this latter condition it possesses a granular appearance and a 

 metallic lustre. 



It was during the experiments of Willougby Smith tl^t an exceedingly val- 

 uable property of selenium was discovered. While making some experiments in 

 his system of cable testing, he was considerably puzzled by the extreme variabil- 



