ELEOTEICITY, KECENT THEOEIES OF. 



239 



ceraber, an Assembly of Notables to be elected 

 by the people, which was designed to inaugu- 

 rate the representative system, at least in form. 

 The enthusiasm and independence with which 

 the Fellaheen voted for their representatives 

 revealed to the Government, and to the in- 

 triguing representatives of the numerous for- 

 eign interests and dynastic factions at Cairo, 

 and their principals in the various capitals of 

 Europe, that the liberal political ideas and na- 

 tionalistic principles of the popular party had 

 taken a deep root in the ininds of the ancient 

 race who once bore the torch of civilization, 

 and who have since tilled their fertile valley 

 under the whip of many masters. 



The Khedive has interdicted the world- 

 known ceremony of the Dosseh. It was cele- 

 brated, every year, on the birthday of the 

 Prophet. The accredited version concerning 

 its origin is this : that an illustrious saint, wish- 

 ing to convince the people of the sanctity of 

 his mission, had the way from his house to the 

 mosque covered with earthen vases ; then, 

 mounting his horse, he proceeded to the house 

 of God without breaking one of the pieces. 

 Those who witnessed the miraculous prome- 

 nade were struck with wonder, and resolved 

 that thereafter the sheik on horseback should 

 pass over a carpet of human bodies. The sa- 

 cred animal could only sanctify the faithful 

 by the contact of its hoof. On the appointed 

 day, every year, an immense crowd has been 

 accustomed to assemble on the ground where 

 the Dosseh is going to take place. English and 

 other foreign tourists have been drawn fre- 

 quently to the horrifying scene by curiosity. 

 The frenzied devotees, often intoxicated with 

 hasheesh, rush with low cries into the lane 

 through which the horse is to pass, which has 

 been kept clear by the police. They prostrate 

 themselves in the way of the sheik as he sits 

 on a splendid white horse, which half a dozen 

 grooms are hardly able to hold. When the 

 bit is let loose, he dashes across the animate 

 pavement. After the sheik has passed, the 

 fanatics, many of them crushed and wounded, 

 disappear as if by enchantment. 



ELECTRICITY, REOKNT THEORIES OF. 

 James Clerk Maxwell enunciated the theory 

 that light is an electrical vibration. The the- 

 oretical ground for this theory is the explana- 

 tion which the two states of electric energy, 

 static and kinetic, afford of the vibratory 

 motion of light. Electricity, when passing 

 through conductors or revolving within the 

 poles of a magnet, is a kinetic force, and when 

 dammed back by an insulator is a static force 

 existing in a state of strain. Light is a form 

 of energy which alternates between the kinetic 

 and the static forms. Its rapid motion through 

 a transparent medium is only comparable to 

 the rate at which electricity travels along a 

 conductor. When it is known that the veloc- 

 ity of light is numerically equal to the calcu- 

 lated rate of the transmission of an electro- 

 magnetic wave-disturbance, as has been the- 



oretically demonstrated by mathematicians, 

 the connection between the two forms of en- 

 ergy, which are found also to touch each other 

 at other points, and to interdepend in many 

 respects, must naturally be supposed to be real 

 and close. That the only known physical 

 forces whose effects are transmitted through 

 such wide media, and at such a high rate of 

 motion, should possess precisely the same ve- 

 locity constant proves that the phenomena can 

 only be referred to the same source. 



Professor Maxwell died before he was able 

 to interpret the true relation between the two 

 great groups of phenomena; but the certainty 

 with which he established that they are the 

 manifestations of one and the same force is the 

 most valuable bequest left by that eminent theo- 

 rist to the scientific world, which brings it to 

 the threshold of a great advance in physical 

 science. That light and electricity are related 

 was first suspected by Faraday, who labored 

 for years to establish his hypothesis. The 

 only result which his many experiments yield- 

 ed was the production of luminosity upon the 

 surface of a dense kind of glass containing 

 borate of lead, by exciting a powerful magnet, 

 between whose poles a beam of polarized light 

 had been projected upon the glass, and then 

 interrupted. This experiment was first inter- 

 preted many years after by Maxwell and Sir 

 William Thomson, and was the experimental 

 basis of the Maxwelliau theory. Many other 

 transparent substances have been found to ex- 

 hibit the same phenomenon in a less marked 

 degree. A feeble luminosity has been dis- 

 cerned, even in common air, between the poles 

 of a magnet similarly excited. Dr. Kerr has 

 recently experimented in the same manner 

 upon opaque bodies, and has shown that when 

 light passes through a film of magnetized iron, 

 thin enough to be translucent, its plane is ro- 

 tated. The main fact which suggests an in- 

 separable relation between light and electricity 

 is the identical value of the velocity of light, 

 which has often been measurer], and of the 

 constant, which expresses the rate at which a 

 magnetic wave-disturbance would travel, which 

 has been calculated from electric measurements. 

 Maxwell's theory explains the fact noted above, 

 that light transmitted through an active elec- 

 tric conductor must change its plane. It re- 

 quires that insulators should be transparent, 

 and conductors impervious to light. Even 

 ebonite, the most opaque of electric insulators, 

 has been shown by Graham Bell to be exceed- 

 ingly transparent to some kinds of radiation. 

 That the co-efficient of velocity of light in a 

 transparent medium should depend upon its 

 electric strain constant is a consequence of the 

 theory. There are certain phenomena which, 

 while showing an intimate connection between 

 light and electricity, have not yet been ex- 

 plained in accordance with the theory. One 

 of these is the remarkable effect of light in 

 reducing the electric resistance of selenium, 

 the light of a candle being sufficient to enhance 



