156 Intelligence and Miscellaneous Articles. 



of electricity ceases, or is much diminished ; and when it continues, 

 it seems only on occasions, when the storm is severe and continues 

 for some time after. The barometer steadily rises throughout. In 

 this part of the world, the fluctuation of the barometric column 

 is very slight, seldom more than two or three-tenths of an inch at 

 a time. 



The average height at Lahore is 1*180, corrected for temperature, 

 indicating, I suppose, above 1150 feet above the level of the sea, 

 taking 30 inches as the standard. 



A large dust-storm is usually preceded by certain peculiarities in 

 the dew-point, and the manner in which the particles of dew are de- 

 posited on the bulb of a thermometer. My mode of taking the dew- 

 point is., to plunge a common thermometer in a little ice, let it run 

 down 20° or 30°, take it out, wipe it dry, hold it up to the light, and 

 observe the bright spot, and continue to wipe off the dew so long as 

 it is deposited and dulls the bulb : at the instant it clears off mark 

 the temperature. This I have compared frequently with Daniell's 

 hygrometer, cooled by means of chloroform, and find them both 

 correspond with the greatest accuracy. 



This is a digression ; but I have no time to arrange, and must 

 therefore put down my remarks as they occur to me. 



The dew-point varies very much, but is usually many degrees below 

 the temperature of air, 20° to 50° or more. 



It also varies according to the time of year. During November 

 last the mean temperature of dew-point was about 47°, that of the 

 air about 71°. 



In January 1850, dew-point 43°; in the air, 61°; and the mean 

 temperature of self- registering thermometer 45°'4. 



In February 1850, mean of dew-point 48°, and air 64°*5. 



April 1850, mean temperature of dew-point so far is about 60°, 

 and the air 84°. 



The sparks or the stream of electricity, as it is seen passing from 

 one wire to the ether, is in some cases, and during high tension, 

 doubled or trebled ; and is never straight, but invariably more or 

 less crooked. 



Various kinds of sparks are seen at times ; one end of the wire 

 has a star ; and from the wire, when held just beyond striking di- 

 stance, a brush is seen curved, which, when viewed through a lens, 

 seems composed of a stream or curved brush of bright globules, like 

 a shower of mercury. 



The manner in which the electricity acts upon the dust and light 

 bodies it meets with in its passage, is simple enough. I suppose the 

 particles similarly electrified and mutually repulsive, and then, 

 together with the whirling motion communicated to them, are 

 whisked into the air. The same takes place when the electricity 

 moves over water. The surface of the water becomes exposed to 

 the electric agency ; and its particles, rendered mutually repulsive, 

 are in the same way whirled into the air. 



At sea the waterspout is thus formed. First of all is seen the 

 cloud descending, and beneath may be observed the water in a cone, 

 misty and agitated ; soon the cloud is seen to approach and join the 



