32 HISTORY OF THE DAUBENY LABORATORY 



(y) One portable thermometer in copper case for taking the 

 water temperature. 



3. Eain Gauges. Made of copper, let into stone bed. 



, x T,. . TT . , , f above ground i foot, 



(a) Diameter 5 in. Height at top J , . . f 



r ( above sea-level 190 feet. 



/n\ T\- -m t e f above ground 20 feet. 



(/3) Diameter 5 in. Placed on roof { , . . c 



( above sea-level 210 feet. 



4. Ozone Cage, for Schonbein's paper. 



5. Anemometer, above roof, by Casella. 



6. River Gauges in the Cherwell. 



(a) 1 20 yards below Magdalen Bridge 1 . 

 (/3) 130 yards above a. A scale of feet marked in 

 cement fixed against a wall. 



Order in which the Observations are taken. 

 Time, 10 a.m. 2 



I. The temperature of the barometer is read off from the 

 attached thermometer, the cistern-level adjusted after gently 

 tapping the instrument, and the height of the column read off 

 on the vernier and entered. The corrections as above are 

 made afterwards. 



3. The solar maximum radiation, and the minimum ther- 

 mometer on the grass and i foot above it, are read and 

 adjusted. 



3. The maximum and minimum, together with the wet and 

 dry bulb thermometers, are read and adjusted. The degree 

 of humidity is found from Bone's tables 3 . 



4. The rain gauge is visited 4 . The rainfall is measured 

 and entered on the spot. 



5. The river temperature on the surface and 3 feet below 



1 This instrument consists of a simple float in a well freely communi- 

 cating with the Cherwell. The float bears a rod graduated in feet and 

 inches, which indicates its position and the height of the water. The 

 graduations are so arranged that zero on the scale corresponds to a mean 

 height ; it is about 186 feet above sea-level. 



2 The observations were taken at 9 a.m. before Jan. i, 1873. 



3 Tables for Mason's Hygrometer, by Wm. Bone, Esq. London : Jones, 

 Optician, Charing Cross. 



4 Should rain be falling at 10 a.m., the rain gauge is visited immediately 

 after reading the barometer. 



