188 Scientific Intelligence — Arts. 



This whistle consists of an air chamber or condenser, of boiler iron 

 sufficently strong to resist almost any pressure, an air-pump, and a 

 whistle similar to the ordinary ones used on locomotives. By means 

 of the air-pump operating into this chamber, a pressure of air is 

 obtained in it of any required amount, — say one, two, or three hun- 

 dred pounds to the square inch. When the air is so compressed, it 

 is made to operate the whistle by simply opening a valve, and gives 

 a distinct clear sound. 



A memorial has been presented to the Treasury Department, 

 signed by njostofthe commanders and pilots of the steam-boats run- 

 ning through Long Island and Fisher's Island Sounds, setting forth 

 the advantages to be derived to navigation from this whistle, and 

 urging that it be introduced into the light vessels, and at all stations 

 where the government intends to afford protection to navigation. — 

 Annual of Scientijlc Discover i/, p. 70. 



27. Curious Electrical Phenomenon. — We learn from a letter 

 from a gentleman connected with the Bay State Mills, at Lawrence, 

 Massachusetts, some facts with reference to a new and curious applica- 

 tion of electricity which has been introduced in those mills. The elec- 

 tricity is generated by the motion of the machinery, and is employed 

 for lighting up the gas burners. It exists in large quantities in the 

 card-rooms, where there are many belts runningon iron- pulleys, and, 

 in the cold dry atmosphere of winter, often producing serious damage 

 to the quality of the cording. The manner in which it was discovered 

 that this electricity could be applied to " lighting up," is somewhat 

 curious. When the gas was first let into the pipes in the mills, one 

 of the overseers discovered fire setting out from one of the pipes near 

 a belt, and on examination it was ascertained that a small stream of 

 gas was escaping. It was surmised that it had been ignited by the 

 electricity, and to prove it, an experiment was tried. Near a large 

 belt in the carding-room was a gas-burner, and on a bench between 

 them there was placed a small quantity of wool, which is a non-con- 

 ductor of electricity. If a person stood upon this wool, reaching one 

 hand within two or three inches of the belt, and touching the gas- 

 burner with one finger of the other, the escaping gas was at once 

 ignited with an explosion like that of a percussion- cap, — the body of the 

 operator thus being made the medium for conducting the electricity. 

 The writer adds, — " We shall be able to make a great saving of 

 expense in the woollen manufacture, as soon as we can discover an 

 effective method of conducting the electricity away from the cards, as 

 we shall then Ire able to dispense entirely with the use of oil on the 

 wool, we shall save at least ^30,000 per annum, when the mills are 

 in full operation." — American Annual of Scientific Discover!/ p . 



