APPENDIX A 33 



the surface is read from a thermometer placed there by the 

 observer on his way to the rain gauge. 



6. The height at which the water stands is noted by refer- 

 ence to the river gauge, and during floods the rise or fall is 

 observed and recorded several times daily. 



7. The direction and force of wind, the kind and amount 

 of cloud, and the weather, as required by Beaufort's scale, is 

 entered. 



8. The ozone paper is removed from the ozone cage, 

 a fresh piece fastened in, and the amount of ozone entered 

 according to the ozone colour scale ; the exposed paper 

 having been dipped in distilled water before comparing it 

 with the scale. 



The observations are entered in oblong tables measuring 

 1 6 inches by 10 inches. Each table is constructed for one 

 month's observations, and the variations of the barometer, 

 thermometer, and rainfall are summarized in curves on the 

 opposite page. 



The continuous series of observations commenced by Tempera- 

 Mr. Hopkins, and carried on and much extended by Mr. 

 Chapman, were found to be of great value when the British 

 Association appointed a special Committee, consisting of the 

 Hon* Ralph Abercromby, Dr. A. Buchan, Mr. J. Y. Buchanan, 

 Mr. J. Willis Bund, Professor Chrystal, Mr. D. Cunningham, 

 Professor Fitzgerald, Dr. H. R. Mill (Secretary), Dr. John 

 Murray (Chairman), Mr. Isaac Roberts, Dr. H. C. Sorby, and 

 the Rev. C. J. Steward, to inquire into and to report upon the 

 Seasonal Variations of Temperature in Lakes, Rivers, and 

 Estuaries in various parts of the United Kingdom, in co-opera- 

 tion with the local societies represented on the Association. 



The records of the temperature of the Cherwell kept at the 

 Daubeny Laboratory were warmly commended by the Com- 

 mittee, who directed especial attention to * Mr. Chapman's 

 magnificent series of mean monthly temperatures, which 

 illustrate very clearly the variations in the seasonal swing of 

 temperature in water in one of the most extreme average 

 climates of the British Islands, taking its low altitude into 

 account. It serves not only to record the variations in 



D 



