THE SANITARY INFLUENCE OF FORESTS 19 
the north-west wind that the milk flow is decreased on windy days. A large 
dairy owner north of Smith River, who weighs each day the amount of milk 
produced by his herd, states that in spring and summer the amount of milk 
falls off as much as 16 per cent during the windiest days when the cattle are 
pastured on exposed fields. 
2. Don and Chisholm, Modern Methods of Water Purification, p. 278, 
give a map showing the way in which salt is carried inland in the west of 
Scotland. See also W. Barr, in Jowrnal of Hygiene, xiv. 119 (1914), on the 
laws regulating the blowing inland of salt spray and spindrift. 
3. Observations were made by L. A. Boodle of the Jodrell Laboratory, 
Kew, on the foliage of seven species of trees and shrubs injured at Llanishen 
in Wales, five miles inland from the sea, by a severe gale accompanied by salt 
spray. Examination showed that the leaves of all the species, whether 
injured or uninjured, contained much more sodium chloride (common salt) 
than the foliage of the same species growing in Kew Gardens. Injured and 
unharmed parts contained the same amount of salt. This is taken up by 
plants from the soil, which in districts close to the sea and for some miles 
inland contains much sodium chloride brought by gales. The distribution 
of the brown discoloration on the leaves indicated wind-withering, due to loss 
of water, and did not seem to be due in any way to the direct effect of salt 
spray. Cupressus macrocarpa and Euonymus japonica were unharmed, whilst 
Thuya, yew, Lawson cypress, common laurel, and Portugal laurel were all 
injured. See Gardeners’ Chronicle, 26th Feb. 1916, p. 119. 
4, See British Medical Journal, 12th Jan. 1901, p. 69, 23rd May 1908, 
p- 1189, 4th Jan. 1905, p. 62, and 3rd Nov. 1906, p. 1165, and The Lancet, 
7th and 14th Jan. 1905. 
' 5. The mountain peat probably did not begin to form till late in the 
Bronze Age. In the Neolithic period the temperature seems to have been 
4° F. higher than now, and the British Isles enjoyed a continental climate 
with prevailing cold dry winds from the north-east. After this, some time 
during the Bronze Age, the climate altered, and has gradually become wetter 
with prevailing westerly winds. Plunkett, in Kilkenny Jowrnal of Archaeo- 
logy, xiii. 587 (1875), states that the cairns, pillar stones, and stone circles on 
Topped Mountain in Fermanagh, which he dates as 1600 B.c., were built on 
the original rock surface, and since then have been covered with peat of the 
thickness of eight feet. He concludes that in the cairn-building time the 
climate was much warmer and less humid than now. The cairns on the 
Dublin Mountains are also covered with peat. The existence of the optimum 
climate in the Neolithic Period and early Bronze Age has been proved in 
other ways. 
6. See Geo. B. Rigg, in Bot. Gazette, \xi. 159 (1916), where comparative 
tables are given of air and soil temperatures of peat-bogs and of arable land 
adjoining. 
7. See A. Henry, “Afforestation of Peat-Bogs and Sand-Dunes,” in Country 
Life, 22nd April 1916, p. 497. This article contains an account of a cheap 
method of establishing maritime pine by sowing seed on cut-over bog at 
Abbeyleix. It was republished, without the illustrations, in a book by P. 
Anderson Graham, Reclaiming the Waste, pp. 118-127 (1916). 
8. See Fernow, U.S. Forestry Bulletin, No. 7, p. 170 (1893), and 
Economics of Forestry, p. 77 (1902). 
9. Economie Forestiére, i, 199, note (1904). 
