FOR THE ADVANCEMENT OP SCIENCE. 147 



a person endeavouring to move the wheels would find a resistance 

 equal to 1501bs. ; the cause of the resistance was this, that the trac- 

 tion upon the engine induced additional friction of the machinery, 

 and that, probably, was one-fifth of the whole amount of friction. 

 If the carriage moved without a train, there would be a passive re- 

 sistance; if a train were attached to it, there would be induced a 

 considerable friction of the machinery. There were, in fact, three 

 causes of resistance — the friction of the carriage, the passive resist- 

 ance, the additional friction by the train ; the first and last varying 

 according to the weight of the train. On the other side there was 

 the expansive force of the steam. The quantity of work done was 

 greater as the velocity was less. He would chiefly apply himself to 

 inclined planes. Great power was required in drawing a train up 

 an inclined plane, but when the train came down the inclination no 

 additional power was gained, because the steam evaporated through 

 the safety-valve. On this account, in addition to the loss of time, 

 inclined planes on railways were highly injurious, and should be 

 avoided. Dr. Lardner stated his entire concurrence in all that had 

 fallen from Professor Moseley. 



A very important discussion arose on the application of our know- 

 ledge of the phenomena of waves to the improvement of the navi- 

 gation of shallow rivers and canals, by Mr. Russell ; the result of 

 whose experiments are detailed in the proceedings of Tuesday, 

 Section A. 



Tuesday. — Mr. Hawkins read a paper on an Improvement on 

 Neper's Rods, for facilitating the multiplication of high numbers, 

 with little liability of error ; the invention of J. N. Cossham, Esq., 

 of Bristol. 



Mr. Daubeny explained the properties of an instrument he had 

 contrived for obtaining sea water at great depths for chemical analysis. 



Mr. Braham explained an improvement he had made in the ma- 

 riner's compass. 



There being no other business before the section, it broke up 

 early. 



Wednesday. — The Chairman read a paper on Naval Architec- 

 ture, sent by Mr. Henwood, of Portsmouth Dock Yard. 



Mr. Price exhibited a model of a new construction of Pad- 

 dle Wheels, he had them placed on his steam vessel, and he 

 could now do 108 miles in eight hours and a half. The paddle rose 

 vertically and the water ran off, and it was also a saving of one- third 

 in fuel and time. These paddle wheels where adopted by the Ord- 

 nance. 



A discussion ensued between Mr. Russell and Mr. Price, which 

 did not terminate until 3 o'clock, when the meeting broke up. 



Thursday. — Mr. Chatfield read a very long essay on Naval 

 Architecture. Mr. Enys gave a most interesting account of the 

 Cornish steam-engines. 



Dr. Lardner then proceeded at great length to detail his plan for 

 steam communication with the United States. After pointing out 



