_Experiments by M. Demoget._--In order that he might compare the intensity of the sounds transmitted by the telephone with the intensity of original sounds, M. Demoget placed two telephones in an open space. He held the first to his ear, while his assistant withdrew to a distance, constantly repeating the same syllable with the same intensity of tone in the second instrument. He first heard the sound transmitted by the telephone, and then the sound which reached him directly, so that comparison was easy, and he obtained the following results. At a distance of 93 yards the original and the transmitted sounds were received with equal intensity, while the vibrating disk was about 5 centimètres from the ear. At this moment, therefore, the relative intensity was as 25 to 81,000,000. In other words, the sound transmitted by the telephone was only 1/3000000 of the emitted sound. ‘But,’ said M. Demoget, ‘since the stations at which we worked could not be regarded as two points freely vibrating in space, the ratio may be reduced by one half on account of the influence of the earth, and the sound transmitted by the telephone may be supposed to be 1,500,000 times weaker than that emitted by the voice. ‘Again, since we know that the intensity of the two sounds is in proportion to the square of the range of vibrations, it may be concluded that the vibrations of the two telephone disks were in direct proportion to the distance, that is, as 5 to 9,000, or that the vibrations of the sending telephone were eighteen hundred times greater than those of the receiving telephone. These latter may therefore be compared to molecular vibrations, since the range of those of the sending telephone was extremely small. ‘Without in any degree detracting from the merit of Bell’s remarkable invention,’ continues M. Demoget, ‘it follows from what I have said above that the telephone, considered as a sending instrument, leaves much to be desired, since it only transmits the 18/100 part of the original power; and if it has produced such unexpected results, this is due to the perfection of the organ of hearing, rather than to the perfection of the instrument itself.’ M. Demoget considers this loss of power which takes place in the telephone to be chiefly owing to the eight transformations in succession to which sound is subjected before reaching the ear, setting aside the loss due to the electric resistance of the line, which might in itself suffice to absorb the whole force.