616 EXPERIMENT STATION RECORD. 



Weafhcr. — Total cloudiness recorded by sim tliermometer, 2,137 hours, or 48 

 per cent ; uuuiber of clear days, 95» Bright siiiishine. — Number of hours re- 

 corded, 2,317 hours, or 52 per cent. Wind. — Prevailing direction, west ; total 

 movement, G0,01(> miles; maximum daily movement, 52!) miles, February 3; 

 minimum daily movement, 18 miles, December 8 ; maximum pressure per square 

 foot, 32.5 lbs., July 20, west. Dates of frost.— Tuast, May 22 ; first, September 

 27. Dates of siunv. — Last. May 11 ; first, November 24. 



The weather of 1906, F. Wakerley {Midland Agr. and Dairy Col., Rpts. 

 Expts. Crops and Stock, 1906-7, pp. 131-134, chart 1). — This is a summary of 

 observations at the Midland Agricultural and Dairy College, Kingston-on-Soar, 

 Notts, on the temperature of the air and of the soil at a depth of 1 ft., and on 

 the rainfall during each month of the year. The rainfall of each month is 

 compared with the average for 32 years. The mean daily temperature for the 

 year was 48.2°, 0.6° below the average for 30 years, and the total rainfall 21.2(» 

 in., about 4 in. below the average for 32 years. The relation of the weather 

 conditions to the growth of the staple crops of the region is briefly discussed. 



Meteorological observations for the year 1906 at the Ploti Agricultural 

 Experiment Station, M. Boulatovitch (Ghodlrhnui'i Otchet Ploty. Selsk. Khoz. 

 Opuitn. Stantzii, 12 {1906), pp. 1-34, 229-23// ) .—Unlike the preceding year, 

 which. was characterized by a marked deficiency of rainfall, the rainfall for 



1906, 21.74 in., was considerably in excess of the mean for the 12 years ending 

 with 1906, 16.1 in. The excess occurred in winter and spring, the rainfall for 

 the autumn being somewhat below the normal and resulting in injurious 

 droughts. Violent downpours of rain characterized the precipitation of the 

 year. The mean relative humidity for the year was 75 per cent, approximating 

 quite closely the mean for 12 years, 78 per cent. The evapoi'ation for the year 

 was 27.56 in., the mean for 12 years being 32.78 in. * 



The mean annual temperature was 9.2° C, or 0.2° C. above the 12-year nor- 

 mal. The maximum temiterature. .31.7° (\, was recorded June 30, the minimum, 

 — 18.5° C, January 4. The maximum temperature of the surface soil was 56.6° 

 C, the minimum. — 14.2°. The average atmospheric pressure for the year was 

 29.22 in., or 0.01 in. below the normal, but the pressure was very variable 

 throughout the year. The number of hours of sunshine recorded was 2,074.2, 

 being 4.5 hours below the normal. 



Meteorological observations, W. Fawcett (Ann. Rpt. I'lib. Card, and Plan- 

 tations Jamaica, 1907, pp. 28, 29). — Summaries are given of observations at the 

 different botanic gardens of Jamaica ou atmospheric pressure, temperature, 

 rainfall, dew-point, and humidity for the period from April, 1906, to March, 



1907, inclusive. 



Meteorological observations, A. W. Bartlett (Rpt, Bot. (lard. Brit. Ouiana, 

 1906-7, pp. 23-29). — Tabular summaries are given of observations on rainfall, 

 temperature, sunshine, pressure, relative humidity, wind movement, and earth- 

 quakes at the Botanic Gardens of British Guiana. 



The influence of forests upon wind velocity, J. Murat (Ahs. in Science, n. 

 ser., 26 (1907), No. 668, p. 518; del et Terre, 28 (1907), No. 10, pp. 252, 253; 

 Rev. Gen. Agron., n. ser., 2 (1907), No. 7-8, pp. 296, 297). — ^A series of observa- 

 tions are recorded from wliich the conclusion is drawn that " the greatest effect 

 which a forest can have ui)on the wind consists in diminishing the wind velocity 

 to leeward of the forest. At 50 meters (164 ft.) this decrease in velocity may 

 amount to 3 to 12 kilometers (4-7^ miles) an hour, which means a reduction of 

 the force by the wind by one degree ou the Beaufort scale. This decrease is 

 felt within 100 meters (330 ft.) of the forest. After that the velocity increases 

 again with increasing distance, and at about 500 meters (1,640 ft.) reaches the 

 force noted before the forest was encountered." 



