As regards the accuracy of the figures here given, it must be noted that at present we know nothing about possible alterations in the errors of the different instruments, as it will not be possible to have the instruments examined and compared until we arrive at San Francisco next year. We have provisionally used the errors that were determined at the Norwegian Meteorological Institute before the expedition sailed; it does not appear, however, that they have altered to any great extent.
The meteorological outfit on the Fram consisted of the following instruments and apparatus:
Three mercury barometers, namely:
One normal barometer by Fuess, No. 361 . One Kew standard barometer by Adie, No. 889. One Kew marine barometer by Adie, No. 764.
Five aneroid barometers:
One large instrument with thermometer attached, without name or number. Two pocket aneroids by Knudsen, Copenhagen, one numbered 1,503. Two pocket aneroids by Cary, London, Nos. 1,367 and 1,368, for altitudes up to 5,000 metres (16,350 feet). Two hypsometers by Casella, with several thermometers.
Mercury thermometers:
Twelve ordinary standard (psychrometer-) thermometers, divided to fifths of a degree (Centigrade). Ten ordinary standard thermometers, divided to degrees. Four sling thermometers, divided to half degrees. Three maximum thermometers, divided to degrees. One normal thermometer by Mollenkopf, No. 25.
Toluene thermometers:
Eighteen sling thermometers, divided to degrees. Three normal thermometers-by Tounelot, No. 4,993, and Baudin, Nos. 14,803 and 14,804. Two torsion hair hygrometers of Russeltvedt's construction, Nos. 12 and 14. One cup and cross anemometer of Professor Mohn's construction, with spare cross. One complete set of precipitation gauges, with Nipher's shield, gauges for snow density, etc.