From September 26, 1882, to September 1, 1883, night and day
uninterruptedly, a watch was kept, in which the officers took part, so
that the observations might be regularly made and recorded. Every four
hours a series of direct magnetic and meteorological observations was
made, from hour to hour meteorological notes were taken, the rise and
fall of the sea recorded, and these were frequently multiplied by
observations every quarter of an hour; the longitude and latitude were
exactly determined, a number of additions to the catalogue of the fixed
stars for the southern heavens made, and numerous specimens in natural
history collected.
The apparatus employed by the expedition for the registration of the
magnetic elements was devised by M. Mascart, by which the variations
of the three elements are inscribed upon a sheet of paper covered with
gelatine bromide, inclination, vertical and horizontal components, with
a certainty which is shown by the 330 diurnal curves brought back from
the Cape.
The register proper is composed of a clock and a photographic frame
which descends its entire length in twenty-four hours, thus causing the
sensitized paper to pass behind a horizontal window upon which falls the
light reflected by the mirrors of the magnetic instruments.
Pages:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25