140 Proceedings of Royal Society of Edinburgh. [sess. 
cases where the sea was “rough,” the thermometer readings are 
liable to a little uncertainty, on account of the motion of the vessel. 
With reference to the observations in the lochs of the Clyde sea- 
area, they were made during a series of trips at different seasons of 
the year, and the results of each trip are placed in chronological 
sequence as far as the geographical arrangements adopted permit. 
The arrangement adopted for presenting these data is that of the 
natural districts into which the physical conformation divides the 
region under investigation. The districts are — (1) the Estuary , 
extending from Bowling to Greenock; (2) the Gareloch ; (3) 
Dunoon Basin, which runs as a trough of about 40 fathoms in 
depth from the Dog Bock at the mouth of Loch Goil, through 
lower Loch Long, past Dunoon, and terminates a little to the north 
of the Cumbraes; (4) Loch Long , above the junction with Loch 
Goil; (5) Loch Goil ; (6) Holy Loch; (7) Kyles of Bute, including 
under this name the shallow water between Ascog and Toward, as 
well as the Kyles proper, and Loch Ridun; (8) Loch Strivan ; (9) 
Arran Basin, which includes the Firth of Clyde, from the south 
end of Arran to the Cumbraes, Inchmarnoch Water, Kilbrennan 
Sound as far south as Davaar Island, and lower Loch Fyne up to 
within one mile of Otter Ferry ; (10) Loch Fyne, above Otter; (11) 
the Plateau, extending from Davaar Island and the Mull of Can- 
tyre across the south end of Arran and Ailsa Craig to the Ayrshire 
coast; and (12) the Channel beyond this plateau. 
The observations are arranged under each of the twelve natural 
districts, as far as possible in regular succession for each trip, from 
one end of the district to the other. As a rule, observations were 
made always in the same position during each trip, and it has been 
considered sufficient to designate these positions briefly in the record 
of temperature. The following statement will serve to fix them 
with precision : — 
Estuary. — Observations made in mid-channel when the places 
specified were just abeam. 
Gareloch. — Helensburgh — Observations made a few hundred yards 
off the pier. 
Row (I.) — In about 12 fathoms, just seaward of Row Point. 
Roiv (II.)— In about 25 fathoms, J mile above the point, and 
in the centre of the loch. 
