92 Mr. S. Earnshaw and the Rev. M. O’Brien’s 
Qndly. Professor Kelland now confesses that his funda- 
mental equations are essentially erroneous. Mr. Earnshaw 
and myself have fully confuted his strange attempt to set up 
the plea of misprint and mistranscription. 
3rdly. Professor Kelland does not defend his equations in 
page 159 of the Cambridge Transactions, vol. vi. 
4thly. Professor Kelland most unguestionably denies the ex- 
istence of a normal vibration in the Edinburgh Transactions, 
vol. xiv. page 396; and neglects taking the normal vibrations 
into account in that memoir, which plainly proves how little 
he then understood of the question of transversal and normal 
vibrations. 
I now therefore am entitled confidently to assert the accu- 
vacy of all my assertions respecting Professor Kelland’s in- 
vestigations. 
In conclusion, I beg to state that I have nowhere charged 
Professor Kelland with dishonesty towards M. Cauchy; and 
that what Professor Kelland calls “ my attack upon him” is 
only my defence against his wnprovoked attack upon me $ and 
that when he took upon him to make a public attack upon me, 
he had no right to expect that I would have been content 
with a * private explanation.” 
Dec. 2, 1842. 
IV. A Reply to Professor Kelland’s Letter of November 1842. 
By S. Earnsuaw, M.A., Cambridge, and the Rev. M. 
O'BRIEN. 
To the Editors of the Philosophical Magazine and Journal. 
GENTLEMEN, 
PROFESSOR Kelland in your present Number [ Dec. 
1842.] seeks to avoid the consequences of our arguments 
by stating that we have been led astray by “a misprint, or 
rather a mistranscription,” and that the quantities we have ani- 
madverted upon ‘ are not equal,” and that he has ‘ supposed 
the axis of y to be that along which transmission takes place.” 
We shall reply to these in a reverse order, 
1. The Professor says he has supposed the axis of y to be 
that of transmission. 
If the Professor will refer to p. 161 of his Memoir (Camb. 
Phil. Trans. vol. vi.), he will find that he there states the con- 
trary to be the case in these words: ‘* so that we might at 
once suppose the direction of transmission to be the axis of 
y, and put éy for 6p; this, however, J shall not do;” and as a 
proof that he did not, we find him near the bottom of the same 
