4:5° 50° 55° 60° 65° 70° 73 



45° 50° 55° 60° 65° 70° 75° 



45° 50° 55° 60° 65° 70° 75 



Each vertical interspace represents one 



decrree Fahrenheit, and the fractional parts of a degree are indicated as exactly as possible in the plotting of the curves, Each fifth 



degree is represented by: a slightly heavier line. The transverse interspaces 



inclosed by the heavier lines represent periods of ten days each, as indicated by the dates on the 



leMand Sid; of the pla'te. The lighter transverse lines, intermediate between the heavier ones, are intended to represent the mean of each ten d^V^. -d the curves of temper- 

 ate are ^ttl with' reference to these lines. The left-hand vertical division is devoted to the air temperatures for i88,. x8Sa and 1883 the m.ddle dw.s.oa to^the surface 

 Zlr temperatures for the sanxe years, thus permitting of a comparison of tl.e two; and the right.haad dimon io the water temperature, for ^884 and ,885. 



