ACOUSTICAL DISCOVERIES. 71 



and more increased. I have here two conical tubes each about 

 six inches long : one of them is open at both ends, the other I have 

 divided into two parts at the node. If I stop these two tubes 

 at the section where they have been divided by placing them on 

 the palm of the hand, and sound the note, we shall find that they 

 will produce the same note, and that this is the note given by the other 

 conical tube open at both ends. I have found by trial the position of the 

 node in these tubes, so that by stopping the tube at that point, the note 

 produced from that short pipe when closed shall be the same as from 

 the longer one open at both ends. If that is the case, we may expect 

 also that by stopping the small end of this pipe we shall get the same 

 note from it, which is the case, so that from those pipes, both closed, 

 one at the larger end and the other at the smaller end, we get the same 

 note produced, and this note is the same as that from an open cylin- 

 drical pipe equal in length to the sum of the two closed conical pipes. 

 Taking tubes of the same length, but with different degrees of 

 taper, we pass from a very low note, which is produced with 

 the tube of greatest taper when the largest end is closed, through 

 a succession of notes to the note of a closed cylindrical tube, then 

 by inverting the tubes, taking them in reverse order, and closing 

 the smaller ends, we may produce a succession of notes still increasing 

 in pitch up to the note of an open cylindrical tube of the same 

 length. 



The CHAIRMAN : I will now ask you to record your indebtedness to 

 Professor Adams for his very able exposition of one of the chapters of 

 Sir Charles Wheatstone's great scientific career. It must have struck 

 all those who have been working in science, ever and anon, that when 

 they fancied they had found something new, they find it was done by 

 Sir Charles Wheatstone years ago. That has happened scores of times, 

 but I am happy to say there is every prospect soon of Sir Charles 

 Wheatstone's published and unpublished papers being collected and 

 presented to the public in a recognized form, so that that danger will 

 in future be avoided. I will now call on Mr. Chappell to give us an 

 account of ancient musical science. 



