acceleration of the pendulum in different latitudes. 177 
Melville Island. 
Only one opportunity presented itself in the course of the 
second voyage of setting up the Pendulum clocks ; this was 
during the detention of the ships at Melville Island, in the 
Polar Sea, in the winter of 1819—1820. 
The time afforded for the observations at this station was 
limited by the nature of the climate alone ; they were ac- 
cordingly continued until the rates of the clocks were ob- 
tained with much accuracy : it has been thought proper, 
therefore, to give a more circumstantial detail of the pro- 
ceedings at this station, than at those of the former voyage. 
As soon as the harbour was determined in which it was 
purposed to secure the ships for the winter, and whilst a 
canal was cutting to admit them through the ice by which it 
was already occupied, its shores were carefully examined, 
with a view to select a suitable spot for an observatory. 
The land was found of little elevation, and generally level, 
except where intersected by ravines, being the courses in 
which the winter’s fall of snow drained on dissolution to the 
sea. The soil, which appeared by the banks of these chan- 
nels to be many feet in depth, consisted of sand intermixed 
with small stones, being the debris of the sandstone rock of 
which the island is composed ; it was at this time consoli- 
dated by the frost, and was harder than the original rock, 
but much the greater part bore evident marks of being 
swampy at times ; and even the more elevated spots afforded 
little prospect of a solid foundation for the clock-stands on 
the return of summer. 
However, as no preferable situation could be found within 
