THE VOYAGE OF H.M.S. CHALLENGER. 
In onlor to form some idea of the trustworthiness of the reduced results, I kept a 
fr\v samples of water, differing considerably in salinity, and determined their densities 
at different dates and under different states of atmospheric temperature. The observed 
densities were reduced in terms of Hubbard’s Table. The results are given in Table IX., 
and show a very satisfactory amount of agreement. It will be observed that in this table 
there are no observations at temperatures of 25° C. and upwards, compared with those at 
moderate and low temperatures. Recent experience shows that, had these been so, the 
deficiencies of Hubbard’s Table would have shown themselves. It shows that for non- 
t ropical waters Hubbard’s Table is sufficiently accurate. 
Table IX. 
Showing the Results of Determinations of the Specific Gravities of the 
same Samples of Water at different Temperatures. 
N. 
T,. 
8,. 
T a . 
S 5 . 
T*. 
s 3 . 
t 4 - 
s 4 . 
t 5 . 
s B . 
t 6 . 
S„. 
.» 
200 
102629 
24-1 
102629 
179 
23-9 
102717 
24T 
102713 
• • • 
• • • 
181 
240 
102656 
24-7 
102655 
182 
24-0 
102630 
24-8 
102627 
... 
... 
1' 1 
24T 
102695 
21 0 
102698 
; . . 
193 
261 
102618 
25*9 
102618 
• • • 
' . . . 
270 
21-7 
102692 
17*2 
102690 
18-6 
102691 
11-4 
102683 
271 
21-5 
102659 
16T 
102651 
17*3 
102653 
18-8 
102652 
272 
21 *5 
102618 
16*8 
102615 
17-8 
102611 
• • • 
273 
21*6 
102583 
16*8 
102578 
17*9 
102584 
• • • 
| 279 
18*5 
102639 
15-6 
102634 
170 
102635 
ii-5 
102633 
... 
| 280 
18-5 
102612 
15*4 
102609 
17-3 
102609 
11-4 
102608 
282 
18*7 
102550 
15-4 
102547 
17*3 
102555 
11-4 
102547 
283 
18*7 
102582 
161 
102582 
1-7 *4 
102585 
• • • 
289 
15-6 
102581 
12*3 
102584 
294 
14*6 
102587 
12*7 
102585 
353 
8-7 
102574 
10-3 
102564 
71 
102567 
7-9 
102564 
7 0 
102571 
5-8 
102575 
357 
80 
102532 
7-2 
102533 
• • • 
A 
120 
102621 
9-9 
102627 
8-8 
102616 
7-7 
102614 
6-8 
102615 
5-9 
102618 
B 
12*4 
102692 
9-9 
102694 
8-9 
102686 
8-0 
102686 
6-9 
102688 
5-8 
102680 
C 
12*4 
102608 
9-8 
102621 
90 
102610 
8-0 
102622 
6-9 
102615 
5-8 
102620 
In thi« table, under column N, are found the sample-numbers of the sea-waters used. 
Under Ti, T„ Ac., arc found the temperatures (centigrade) at which the specific 
gravities S,, S», &c., were obtained. 
I he results of the investigation have been placed on the .accompanying chart and 
w*tion», from an inspection of which a general idea of the distribution of density 
in the ocean can be formed. The discussion of the bearing of these results on ocean 
physics is deferred for the present. 
