164 Scientific Proceedings, Royal Dublin Society. 
Tasie 19.—One-foot Pipe. (1.) 5 to 8 p.m. 
i So Wieden | Et eaeMediem 
5 
No. Te W E No. 9p W E 
inch ° ° | 
-200--249 5 70:1 3-2 6er. 5 54:5 3:9 9er. 
250-299 4 72°3 oy | 8 3 58-2 1:0 12 
-300—"399 11 70°6 3°5 12 14 61:4 2°8 14 
-400—-499 15 74:3 3-2 15 17 68:6 3:5 17 
-500-"599 7 77:1 2°9 7 9 74:3 5:4 21 
600-:699 10 79°5 2-9 22 8 71 57 24 
-700 & over 8 82°3 2-2 oT 9 82:6 75 32 
Total, . 60 75-4 2:9 16 65 69:3 4:3 19 
(2.) 8 to 11 p.m. 
-150--199 7 | 6x0 4-0 Sgr.|| 6 | 53-2 2:9 6gr. 
-200-"249 8 | 65:1 2°9 6 S| oR || 29 9 
-250—-299 8 | 64:0 3-2 9 8 | 57:3 4+] 10 
-300--349 | 12 | 69-8 3-6 10 13 | 62-0 2:8 11 
-350-"399 5 |) ila 3:5 ili 6 | 69:5 5-7 12 
“400-449 6 | 74:5 22 12 6 | 67:9 4:7 15 
“450-549 9 | 75-4 3:7 17 8 | 72:6 4:6 18 
Total, . | 55 | 69:5 3:3 10 55 | 62:0 3:8 12 
The results of Table 18 differ from those of Table 16 in one 
important respect: that when the differences of vapour-tension, 
the relative humidity, and the water-temperatures are about the 
same from 5 to 8 p.m. as they are from 8 to 11 p.m., the evaporation 
in the pipe will be about the same in the two intervals; whereas 
under the same equalities the open cup will lose considerably 
more from 5 to 8 p.m. than from 8 to 11 p.m. Table 19 is in effect 
much the same as Table 17, excepting of course that the observed 
evaporation is less. In both cases when 6 is small the temperature 
of the water is much less for low relative humidities than for high ; 
but as 0 increases the temperature of the water for a low relative 
humidity more and more approximates to the temperature for a 
