HOW SMOKE DIMINISHES THE HOURS OF SUNLIGHT.

Bush Advocate, Volume XXI, Issue 297, 19 June 1909, Page 6

HOW SMOKE DIMINISHES THE HOURS OF SUNLIGHT.

That- tin- .Mnokc which z'ises from the. chimuey.s of a city in winter greatly diminishes the practical duration of sunlight is shown by a comparison of observations just completed in the centre of London, at KeAv, a few mik-s to the west, and at Greenwich, ;i few miles to tho east. The annual number of. hours of sunshineis: At Kew, 3339, or 31 per cent, of tho maximum possible number; at the cenlm of London, 1027 hours or_ 23 per cent.; and at Greenwich 1227 or <• 27 per cent. Hence the centre, of London enjoys 372 hours (8 per cent.) of sunshine less than Kew, and 200 (4 per cent.) less than Greenwich: In winter the deficiency of sunshine in the .centre of London rises to 11 per cent. At Hamburg, observations extending over 11 years show an average annual number of 108 days without, sunshine. At al .seasons, but especially in winter, the air. of- Hamburg 1 is filled with smaller or larger particles of .soot. The result is that Hamburg annually enjoys only 1236 .hours of sunshine, or 28 per cent, of the maximum possible number, _while Berlin enjoys 1672 hours, or 37 per j ' cent.