Polytechnic Associatiox Proqeedings, 949 



The extraneous current was observed to flow in waves of fifteen 

 minutes duration, leaving the circuit entirely open at the expiration 

 of each wave, and resuming its intensity after a lapse of a few 

 seconds. These intervals were accounted for on the supposition 

 that corresponding lulls of the wind occurred at some point along 

 the line. 



Toward dusk, after the intensity of the current had decreased 

 considerably, it was deemed safe to replace the relay in circuit, 

 which being done, the line worked unexceptionably well to Fort 

 Laramie without the aid of a main battery at either end. 



This phenomenon is quite difierent to that of the aurora borealis, 

 as the latter is nearly always fitful and irregular in its manifesta- 

 tions, while the former aflbrds a comparatively steady current, by 

 which the line can be readily worked without "change of adjust- 

 ment during the continuance of the wave. 



This example of frictional electricity induced by the wind flow- 

 ing parallel with a long stretch of line has probably never been 

 witnessed elsewhere with the same degree of intensity, as there is 

 no other line on this continent of an equal length which traverses 

 such a level, unbroken geographical surface, over which the wind 

 could have a sweep so continuous and uninterrupted. 



In relation to the item on "Artificial Gems," Dr. Vanderweyde 

 remarked that imitations of diamonds are made of heavy flint glass; 

 they are sometimes called "paste." Glass without lead will not 

 work easily. The Alaska diamond and the California diamond are 

 only the silicate of lead, with a slight trace of soda. Jewellers 

 say that when this imitation is worn by a lady at a party, no one 

 can tell the diflerence between it and the original diamond. One 

 test for a diamond is by tasting it, when the genuine will feel very 

 cold. Glass is a poor conductor of heat, and after a few minutes 

 it loses its luster. By putting in chemicals, the colors can be easily 

 imitated. Another way to examine the stones is to view them 

 through a magifying glass, and if no air-bubbles can be seen, they are 

 of the best quality, for in pm-e gems no imperfections are seen. 

 Twenty yeai's ago artificial diamonds could be easily detected, as 

 they were whiter than the real gems, which have a peculiar dai'k 

 transparency. 



Mr. D. W. Bradley stated that cheap stones, such as are sold " by 

 the peck," are pressed when hot into the desired pattern, and then 

 cut or ground. 



