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15 minutes to 50 millims., in the subsequent '25 minutes tliere was not a leakage of half a millimetre. On 

 returning to the instrument on the following morning (Julj- 30) it was found, however, that the leakage 

 had amounted to 280 millims. in 11 hours 12 minutes. 



Rates in the Antarctic. 



The sidereal chronometer No. 6711 by Kui.LBERG was employed and connected up with the electro- 

 magnet, the current being supplied by two Obaeh dry cells. 



A portable transit instrument was set up in the Absolute Magnetic House for the purpose of observing 

 stars at the commencement and ending of the observations for determining the rate of the chronometer ; 

 but the persistent bad weather made these observations impossiljle, so that the only rate availalile for the 



Inteiior uf (Jbservation Hut, showing — 



1. Open U -tube manometer. 2. T-square for reading-otF same. 



.3. Pendulum a])paratus. 4. Brick pier. b. Exhausting pump. 



sets of pendulum observations taken on July :il and August 1 is that oljtained by comparison with the 

 " Discovery's " marine chronometer on board. 



The rate of chronometer No. 6711 in England, Australia, and New Zealand was small and uniform, and 

 the comparisons with the "Discovery" chronometers in Winter Harbour during 1902 and 1903 indicate 

 that its rate still remained small and uniform. Soon after the "Discovery" had reached her winter 

 quarters this chronometer was set going in the Physicist's cabin, and compared from time to time with the 

 marine chronometers in charge of the Navigator, Lieut. A. B. Armitage. The average temperature within 

 the cabin was 52° F., seldom varying b' on each side ; although the temperature in the observing hut was 

 much lower, it was kept as uniform as possible, and the temperature of the chrcjiiometer frequently noted 

 during the observations. 



