NO. 6.] INTRODUCTION. CHRONOMETERS. XIX 
Longitude, and Rate of Chronometers. 
The expedition was equipped with 3 Mean Time chronometers: Kudter 
24, belonging to the ship, Hohwi 639 lent by the University Observatory in 
Christiania, and Iversen 961, lent by the maker, Mr. Iversen in Bergen. A 
fourth box chronometer, Frodsham 3555, lent by the Norwegian Meteorologi- 
cal Institute, was regulated to Sidereal Time some time before the departure 
and began with a small Josing rate, which, however, continually increased 
during the first winter, and reached the inconveniently large value of between 
5 and 7 seconds a day. It was not used for the observations of stars but 
only for some magnetical observations, and served for the daily comparisons 
by coincidences. These four chronometers will be designated in what follows 
by Kt, Hiv, Iv and Fr respectively. 
There were also on board a number of pocket chronometers and watches, 
one of which was always used for the astronomical observations and com- 
pared with Hiv, generally before and after each observation. The observation 
watch was also compared daily with Hi at the time of comparison for the 
box chronometers. 
The box chronometers were placed on two shelves in Lieut. Scort-Han- 
sen’s cabin, Hw and Fr only 16 cm., Kt and Jv 60 cm. above the deck. A 
thermometer which was placed in the lower shelf with the bulb 17 cm. above 
the deck, was read off at the time of the daily comparisons. In the same 
cabin was also a thermograph, 80 cm. above the deck, which was working 
almost continuously from 1893 July 5 to 1896 August 10. The thermograph 
was compared daily with a thermometer placed by its side and with the thermo- 
meter in the lower chronometer shelf. By means of this last comparison and 
the daily reading of the thermometer in the shelf, which can be compared 
with the thermograph-sheets for the same time, the mean temperature of the 
two lower chronometers can be determined with sufficient accuracy. 
Between the last Time Signal from the Christiania Observatory received 
at Vardé 1893 July 19 and the first after the return, received at Tromsé 
1896 August 23, a good many observations were taken which can be used 
8 y 
