acceleration of the pendulum in different latitudes. 187 
From the Tables A. and B. are derived the following 
results. 
By Transits of 
Vibrations per diem. 
Pendulum i, in Clock 2. 
Pendulum 2, in Clock 1. 
The Sun, S. of Zen. 
The Sun, N. of Zen. 
Arcturus 
a Lyras 
« Aquilas 
Mean of 
\7 days, 86462,583 
7 86462,236 
7 86462,61 
7 86462,25 
7 86462,259 
Mean of 
f 14 days, 86620,293 
7 86620,612 
8 86620,672 
9 86620,578 
9 86620,625 
Each result being given a value proportioned to the num- 
ber of days of which it is the average, the mean results are 
of No. 1 pendulum 864,62,3876, and of No. 2 pendulum 
86620,523 vibrations ; by adding to these numbers the cor- 
rections due to the elevation above the sea, being +0,1443 
to No. 1, and +0,1416 to No. 2, a final result is obtained; 
that No. 1 Pendulum vibrating in Clock No. 2 at Melville 
Island would make 86462,5289 vibrations, and No. 2 Pendu- 
lum in Clock No. 1, 86620,6646 vibrations, in a mean solar day, 
in vacuo, at the level of the sea, the temperature being 45 0 . 
The latitude of the spot where the preceding observations 
were made was 74 0 47' 12,4", deduced by a mean of 39 me- 
ridian altitudes of the sun, observed by Captain Parry and 
Mr. Beechey, with reflecting circles and sextants with an 
artificial horizon ; the results have been re-computed since 
the return of the Expedition, using the table of atmosphe- 
rical refractions, published by Dr. Young in the Nautical 
Almanack of 1822 ; the elements of these observations are 
given in the Appendix to the Narrative of the Voyage, pages 
Ixxxviii and lxxxix. 
B b 
MDCCCXXI. 
