THE 
VOYAGE OF H.M.S. 
CHALLENGER. 
PHYSICS AND CHEMISTRY. 
REPORT on the Deep-Sea Temperature Observations obtained by the 
Officers of H.M.S. Challenger, during the years 1873-76. 
It has been deemed advisable to publish, for the convenience of scientific men, the whole 
of the deep-sea observations of temperature made during the voyage of the Challenger. 
These are given in detail in the accompanying series of 263 plates, which show the 
latitude and longitude of the Station ; the depth in fathoms of the bottom ; the date 
when the serial temperatures were taken ; the depth at which each temperature was 
taken ; the No. of the thermometer ; the temperature actually observed read to quarter 
degrees ; the error of the thermometer ; and the temperature corrected for instrumental 
error only. 
These temperatures were plotted on the squares, as represented on each Plate, by 
Staff-Commander Tizarcl, R.N., simply as observed and corrected for instrumental errors, 
just as has been done in the case of the Challenger Meteorological Observations , 1 no 
attempt being made to correct even the most obvious errors of observation. Thus on 
PI. XVIII. the temperature of 46°‘2 at the depth of 700 fathoms, is plainly 5 D, 0 too 
high ; and on PI. XXII. the temperature 43 o, 0 at the depth of 450 fathoms is 10°’0 too 
low. These, however, are printed as recorded in the Observation Books, it being left 
to the specialist, who may have occasion to discuss the observations, to make for himself 
all such necessary corrections. A curve is then drawn through the observations as 
plotted libera manu, and on examining the curves on Pis. XVIII. and XXII., it will be 
found that allowance has been made for the errors of observation referred to above. 
From these curves a new set of temperatures have been taken, which are printed on 
the line in the Plate named “ Temperature from Curves.” It is the last temperatures 
1 Nar. Claall. Exp., vol. ii. 
(PHYS. CHEM. CHALL. EXP. — PAKT III, — 1884 .) ^ 
