REPORT ON METEOROLOGICAL OBSERVATIONS. 285 



XXX. — Report on the Meteorological Observations made at 

 Carnwath, Lanarkshire, on the Influence of Forests on 

 Climate, particularly Rainfall. By Alexander Buciian, 

 M.A., F.E.S.E., Secretary of the Scottish Meoteorological 

 Society. 



In carrying out this inquiry Mr Maclean of Carnwath very 

 materially assisted the Committee by placing three stations at their 

 disposal. Dr Cleghorn and Mr Buchan visited the three places, 

 and fixed on one which presented conditions of a very favourable 

 character. The forest selected contained about G2 acres, and a 

 little outside, to the north-west, was a green knoll called Gallowhill, 

 quite clear of trees. In the interior of the wood, and 320 yards 

 distant, was another knoll called Winterlaw, of precisely similar 

 character as regards height, exposure, and relation to the ground 

 immediately surrounding it. Immediately on the top of the western 

 slope of this knoll was a bare patch about fifty feet in diameter, 

 which was surrounded on all sides with trees of various sorts, 

 varying from forty to fifty feet in height. The growth of the 

 green sward and of the plants around showed that the situation was 

 well fitted for the inquiry. Two complete sets of meteorological 

 instruments were procured, with proper protection in Stevenson's 

 louvre-boarded boxes, exactly similar to each other. The instru- 

 ments, consisting of maximum and minumum thermometers, and a 

 hygrometer, were placed — one set on each knoll — at exactly the 

 same height, viz., 4 feet above the ground. The observer, Mr Currie, 

 than whom no better could be named for intelligence, care, and 

 accuracy, began the observations on 16th September 1873, and these 

 were continued till the end of September 1874. The instruments 

 showed the highest and lowest temperature each day, together with 

 the temperature of the air and the temperature of evaporation at 9 

 a.m. and 9 p.m. The precise points to be elucidated were the con- 

 ditions of the atmosphere as regards temperature and moisture out- 

 side the wood as compared with the interior of the wood. The 

 results of the observations are given in the table accompanying this 

 report, the more imrjortant points of which will now be detaded. 



Remits of the Self-Registering Thermometers. — At Winterlaw, in 

 the interior of the wood, the highest temperature during the period 

 was 79°-4 on 18th July, and the lowest 19°-0 on 11th February 



