84 
earth and sun, was nearly right, so nearly that an increase of 
one-tenth of a day in the perihelion passage gave an impossi- 
ble value for the sine of this angle. The orbit and all the cir- 
cumstances were particularly favourable for Newton’s method ; 
which was, therefore, applied with considerable modifications. 
«¢ Without a complete discussion of all the observations 
the result cannot be regarded as final. It is, therefore, need- 
less to dwell upon the subject, at present, to any greater 
length. Part of what is here inserted may be too common- 
place to bring before the Academy. You will oblige me by 
pruning as you judge proper. 
‘«* The rate of motion at the perihelion was fifty-one miles 
per second. 
*¢ With sincere thanks for your kind encouragement, 
‘*] am very truly yours, 
‘* ANDREW GRAHAM. 
“ Sir W. R. Hamilton, 
esr ice. 
The Rey. Charles Graves made the following communica- 
tion on the comparison of adjectives in the ancient Irish lan- 
guage :— 
‘*The most eminent Irish grammarians have constantly 
denied the existence of a superlative form, as distinguished 
from the comparative. I was, therefore, surprised to find some 
undoubted instances of the use of a distinct superlative form oc- 
curring in an ancient Irish tract, in the study of which I was en- 
gaged more than two years ago; and since then I have continued 
to collect such other examples of this kind as I met with, in- 
tending to bring the subject under the notice of the Academy. 
‘¢On looking, however, to the ‘Celtic Grammar,’ lately 
published by Professor Zeuss, I found that I had been antici- 
pated by that learned and accurate scholar in the statement 
of this fact. He shows that in the old Welsh language there 
was a superlative ending in am, of which he adduces hinham, 
