MR. J. PRESTWICH ON SUBMARINE TEMPERATURES. 
621 
At a depth of 300 brasses in March a temperature of . 
33 
600 
33 
33 
12-7 Cent. 
12-6 
The only temperature-observations made in the eastern basin of the Mediterranean 
previously to 1869, with the exception of two of Wullerstorf, are those of Admiral 
Speatt. They extend from Malta to Alexandria, and from the Grecian archipelago to 
the Gulf of Syrtis, forming for this section of the Mediterranean a series complemental 
to those made in the western section by D’Urville, Berard, and Aime. The results he 
obtained are also, when corrected, in close agreement with those of these several 
observers. His first experiments were made in ZEgina Bay in 1845, in connexion with 
the natural-history researches of Edward Forbes, and extended only to a distance of 
three miles from shore. Allowing for a gain of 0 o- 5 or 1° in hauling lip the silt, the 
corrected readings will then give as the general results : — 
For Forbes’s Zone I. (1 to 12 feet) a temperature of . 55 to 82 Fahr. 
„ „ II. (at and near 120 feet) . . . . 69 to 70 
„ „ III. ( „ 330 feet) . . . 56 to 57 
„ „ VII. ( „ 1260 feet) . . . 54-5 to 55 
Three other experiments in the seas of Greece gave him the following readings : — 
O 
1080 feet (four miles off Nio) . . 55*51 or, allowing for gain in hauling 
1200 „ (seven miles off Andros) 55’5 > up through warmer waters, 
1260 „ (three miles off iEgina) 55*5 J of from 54°*5 to 55°. 
In the shallower waters of the archipelago he found “ the temperature of the 
intermediate depths between 100 fathoms and the surface range from 55° to 76°, and, 
indeed, in the summer season sometimes up to 80° and 86° in the littoral waters of 
enclosed gulfs and shallow bays.” 
A set of serial observations off Crete, made later with unprotected self-registering 
thermometers, gave readings as under (these, when corrected for pressure, agree, with 
the exception of the fourth, which seems a doubtful reading, very closely with those of 
Berard in the southern portion of the western Mediterranean basin*): — 
Temperature at depths in the Mediterranean off the N. W. Coast of Crete. 
Uncorrected. Corrected for pressure. 
Surface in the month of June 
o 
. . 73 Fahr. 
73° Fahr. 
At a depth of 120 feet . 
. . 68 
67-9 
„ 300 „ . . . 
. . 63 
62-7 
„ 600 „ . . . 
. . 59f 
59-4 
„ 1200 „ . . . 
. . 59f (?) 
59? 
„ 7440 „ . . . 
. . 59± 
55-2 
Admiral Spratt says that he found this temperature of “ about 59° in all depths from 
300 down to 2000 fathoms.” In the extreme eastern portion of the Mediterranean 
* Nautical Magazine for 1862, p. 10 ; e Travels and Researches in Crete’ (London, 1865), vol. ii. App. p. 332. 
4 O 2 
