30 On the Distribution of Temperature in the Gulf Stream. 
as they approach the land, was shown to belong to a state of 
equilibrium of temperature which would be assumed by a mass 
of water having warm water above it and cold water below it, 
to be represented by a logarithmic curve, and therefore to be due 
to conduction. That in the Gulf Stream varied according toa 
different law, indicating a disturbance of equilibrium. Diagram 
No. 1 shows the distribution of temperature with depth, in the 
water between the shore and Gulf Stream, as deduced from the 
observations of Lieutenant G. M. Bache. The ordinates of the 
curve represent the depths, and the abcisse the temperatures. 
The depths, in fathoms, are written at the side of the diagram, 
and the temperatures by Fahrenheit’s scale, at the top. The 
position at which the temperatures at various depths, recorded in 
this diagram, were obtained, was in latitude 36° 15’ north, longi- — 
tude 73° 52’ west, on the section intended to be made from Cape 
Henry perpendicular to the axis of the stream. ‘This curve, and 
others of the same kind, were compared with the logarithmic 
eurves which would best represent the observations, and their 
close coincidence with them shown. The curves were deduced 
by least squares, from an ingenious investigation by J. H. Lane, 
Esq., then of the Coast Survey, now one of the chief examiners, 
in the U. 8. Patent Office. 
Diagram No. 2, taken also from Lieut. G. M. Bache’s observa- 
tions, shows the character of the curve of distribution near the 
axis of the Gulf Stream. These particular results were obtai 
in one of the positions on the Cape Henry section, in latitude — 
3 : | 
° 53’ N., and longitude 73° 34/ W. 
The projecting form of the curve towards 300 fathoms, and 
the moderate change of temperature, ten degrees, from 150 to 40 
fathoms, shown in that diagram, are characteristic features of the 
distribution in similar positions. The change from the surface to 
150 fathoms was 17° Fahrenheit. Diagram No. 3 represents @ 
corresponding curve to No. 2, from Lieut. Maffit’s observations on 
the Charleston section, in latitude 33° 58’ N., longitude 73° 
W. In this the change between 100 and 40 vn fathoms is still 
less than in the former case, being but five degrees. 
Diagram No. 3 bis shows the curve comespondiog to that of 
diagram No. 1, but on the Charleston section nearer to the shore 
than the axis of the stream in latitude 31° 48’ N., longitude 
78° 47’ W. 
2. Distribution of temperature at the same depth, on sections 
perpendicular to the axis of the Gulf Stream. 
Diagram No. 4 contains the results of observations on the sec- 
tion perpendicular to the stream from Sandy Hook, and shows the 
mode in which the observations were discussed. The positions 
where the temperatures were observed are marked at the head of 
the diagram, and above them the distance from Sandy Hook in © 
nautical miles. The temperatures are marked on the side of the 
