8 Wilde, On Aerial Locouiotion. 



pi cssures varying from 20 lbs. to 120 lbs. per sq. in., the rate 

 of discharge was approximatel)- in accordance with the 

 proposed formula of Mr. Froude, for the discharge from 

 a simple orifice. 



20. Experiments were next made to ascertain if the 

 rate of discharge of steam was influenced by a powerful 

 current of electricit}- transmitted through a helix surround- 

 ing a vulcanite discharging tube. It was found that 

 electricity had no influence on the rate of discharge under 

 these conditions. The same result was obtained when an 

 iron tube forming a powerful electro-magnet was substi- 

 tuted for the one of vulcanite. 



21. The like negative result was also obtained when 

 air at 120 lbs. pressure was discharged through a thermo- 

 meter tube 24 inches long and coiled with a helix of the 

 same length through which a powerful electric current 

 was transmitted. 



22. An experiment was made to ascertain if the rapid 

 molecular extensions and contractions of a tubular 

 U-formed electro-magnet, in which air of eight atmos- 

 pheres was compressed, would manifest any reaction when 

 a powerful electric current alternating 7,000 times per 

 minute was transmitted through the coils. The limbs of 

 the electro-magnet were nine inches long and were sus- 

 pended horiz.ontally b\' means of a fine cord. When the 

 electro-magnet was excited, no deviation from the perpen- 

 dicular occurred to indicate any reactive force of the 

 enclosed air from the free ends of the magnet. 



23. Experiments were also made on the reactive 

 force produced by the explosion of a mixture of coal gas 

 and air, contained in a specially constructed cylinder of 

 steel. The cylinder was five feet high and three feet in 

 diameter. One end of the c}-Iinder was pierced with a 



