nd sundry short expeditions, occupied nearly three
weeks. We had continued the computation of our observations at every
possible interval. It is to be understood that we had one detached
pendulum swinging in front of a clock pendulum above, and another
similarly mounted below; and that the clocks were compared by
chronometers compared above, carried down and compared, compared
before leaving, and brought up and compared. The upper and lower
pendulums had been interchanged. It was found now that the reliance
on the steadiness of the chronometers was too great; and a new method
was devised, in which for each series the chronometers should make
four journeys and have four comparisons above and two below. This
arrangement commenced on the 19th June and continued till the 20th. On
the 26th we packed the lower instruments, intending to compare the
pendulum directly with the upper one, and sent them up the shaft: when
an inexplicable occurrence stopped all proceedings. The basket
containing all the important instruments was brought up to the surface
(in my presence) on fire; some of the instruments had fallen out with
their cases burning. Whether a superstitious miner had intentionally
fired it, or whether the snuff of a candle had been thrown into it, is
not known. Our labour was now rendered useless. On the 28th I packed
up what remained of instruments, left for Truro, and arrived at Bury
on July 1st. During our stay in Cornwall I had attended a 'ticketing'
or sale of ore at Camborne, and we had made expeditions to the
N.W. Coast, to Portreath and Illogan, to Marazion and St Michael's
Mount, and to Penzance and the Land's End. On July 3rd I saw Mr
Cropley in Bury gaol, and went to Cambridge. On the 4th I was admitted
A.M., and on the 5th was admitted Major Fellow.

"I had engaged with four pupils to go to Orleans in this Long
Vacation: my brother William was also to go. One of my pupils, Dobbs,
did not join: the other three were Tinkler, Ogilby, and Ibbotson. We
left London on July 9th, and travelled by Brighton, Dieppe, Rouen, and
Paris to Orleans. At Paris I saw Bouvard, Pouillet, Laplace and
Arago. I had introductions from Mr Peacock, Mr South, Mr Herschel, Dr
Young; and from Professor Sedgwick to an English resident, Mr
Underwood. On the 19th I was established in the house of M. Lagarde,
Protestant Minister. Here I received my pupils. On the 28th I
commenced Italian with an Italian master: perhaps I might have done
more