366 Proceedings of the British Association. 



m 



severally affect the vibrations of the columns of air, and conse- 

 quently the sound produced. 



29. Professor Whealstone on Speaking Machines. The au- 

 thor noticed the attempts made by the Germans to form pipes 

 ■which would imitate the vowel sounds. De Kemplin imitated 

 different sounds with a conical tube, more or less covered at the 

 mouth. The author observed, that the difference of the vowel 

 sounds depended solely on the relative size of the cavity of the 

 mouth, altered by the tongue and the opening of the lips. Wil- 

 lis, by a tube (containing a reed), altered in capacity by sliding, 

 extended the scale to other vowel sounds. He proposed a new 

 mode of classifying the consonant sounds. He exhibited a copy 

 of the machine of De Kemplin, in which the mouth is imitated 

 by an India rubber bell, and consonant sounds produced. 



SO. Mr W he well on a new Anemometer. The object kept in 

 view in the construction of this instrument, is to measure the 

 variation of intensity corresponding to the time. The instru- 

 ment was exhibited. It consists of a small vane, with sails like 

 a windmill, turning to the wind, and round its axis. Its circu- 

 lar motion is thus converted into a much slower vertical motion. 

 A pencil is moved which traces a line on a paper cylinder, shew- 

 ing the direction and strength of the wind. Sir John Ross made 

 some remarks on his own method of judging of the intensity of 

 wind at sea, and of the means adopted by him, during his last 

 voyage, to register the direction of the winds, and their velocity, 

 combined with the state of the weather, barometer, and thermo- 

 meter, from observations as accurately made as circumstances 

 w r ould admit of, every half hour. He expressed his doubts of 

 the utility of the instrument in the Arctic regions ; but said 

 that it would have been desirable to have had such an instru- 

 ment with him in his last voyage, in order to test its utility and 

 accuracy. 



31. Professor Lloyd detailed his magnetic observations in 

 Ireland, made in connexion with Captain Sabine, which were 

 undertaken at the request of the Association. They consisted 

 of observations of the dip and force. The lines of equal dip 

 were pointed out, with irregular variations of intensity, probably 

 depending on atmospheric causes not yet understood. The 

 ines of equal intensity were in some measure determined. 



