212 The Hon. J. W. Strutt's Remarks on 



If in (VII.) we further put S=0, 



= w 



b= Ia/i 



ww^r ' ' ' (X-) 



a result which Dr. Sondhauss applies to cylindrical tubes closed 

 at one end. This being admitted, it readily follows that for a 

 pipe open at both ends, 



. . (XL) 



L(L+V°-) 



An extension is next made to the case of more than one neck, 

 but it will not be necessary for my purpose to repeat the for- 

 mulae. A few days before I saw Dr. Sondhauss' s work I had 

 myself completed a paper on a similar subject, which has since 

 been sent to the Royal Society. The formulae there given were 

 in the first instance obtained theoretically, though some of them 

 were afterwards verified by a rather laborious series of experi- 

 ments. But on the present occasion I shall leave the theory on 

 one side, and wish only to discuss some differences between the 

 results of Dr. Sondhauss and my own, regarded from an experi- 

 mental point of view. The rational formula corresponding to 

 (VII.) is 



where, however, S has not quite the same meaning as with Dr. 

 Sondhauss, but includes the volume of about half the neck, and 



is therefore nearly identical with the ( S-i J of (VII.). Oa 



this understanding (VII.) may be written 



__ a g* / VTT v 



n ~ 6-0988 sVL + tf*' • • ' • ^ n ') 



while (A) expressed in numbers is 



__ a <r* ... 



n " 6-2832 SVl + -8863v^" '■'' ' ■ 



If cri be very small against L, 



<r* 



n =ems-m> tvin.) 



6-2832 S* L* 



But if L be very small, 



(B) 



