. Arctic explorations: the second Grinnell expedition in search of Sir John Franklin, 1853, '54, '55. haps forty broad, and aboutthirty feet above the water-line. Here we raised fourwalls of granite blocks, cementing them together withmoss and water and the never-failing aid of frost. Onthese was laid a substantial wooden roof, perforated atthe meridian and prime vertical. For pedestals wehad a conglomerate of gravel and ice, well rammeddown while liquid in our iron-hooped j)emmican-casks,and as free from all vibration as the rock they restedon. Here we mounted our transit and theodolite. The
. Arctic explorations: the second Grinnell expedition in search of Sir John Franklin, 1853, '54, '55. haps forty broad, and aboutthirty feet above the water-line. Here we raised fourwalls of granite blocks, cementing them together withmoss and water and the never-failing aid of frost. Onthese was laid a substantial wooden roof, perforated atthe meridian and prime vertical. For pedestals wehad a conglomerate of gravel and ice, well rammeddown while liquid in our iron-hooped j)emmican-casks,and as free from all vibration as the rock they restedon. Here we mounted our transit and theodolite. The magnetic observatory adjoining, had rather moreof the affectation of comfort. It was of stone, ten feetsquare, with a wooden floor as well as roof, a co|)perfire-grate, and stands of the same Arctic breccia asthose in its neighbor. No iron was used in its con-struction. Here were our magnetometer and dipinstruments. 116 C THE OBSERVATORY. 117 Our tide-register was on board the vessel, a simplepulley-gauge, arranged with a wheel and index, anddependent on her rise and fall for its rotation/^^^ ?. BRIG IN HARBOR. Our meteorological observatory was upon the openice-field, one hundred and forty yards from the was a wooden structure, latticed and pierced with 118 - THERMOMETERS. auger-holes on all sides, so as to allow the air to passfreely, and firmly luted to its frozen base. To guardagainst the fine and almost impalpable drift, which in-sinuates itself everywhere, and which would interferewith the observation of minute and sudden changesof temperature, I placed a series of screens at rightangles to each other, so as to surround the innerchamber. The thermometers were suspended within the centralchamber: a pane of glass permitted the light of ourlanterns to reach them from a distance, and a lens andeye-glass were so fixed as to allow us to observe theinstruments without coming inside the screens. Theirsensibility was such that when standing at 40° and 50^below zero, the m
Size: 1178px × 2120px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1850, bookpublisheretcetc, bookyear185
