Now, there is much evidence to show that there has been a considerable
increase in the amount of cloud, and consequent decrease in the amount
of sunshine, in all parts of our country. It is an undoubted fact that
in the Middle Ages England was a wine-producing country, and this
implies more sunshine than we have now. Sunshine has a double effect, in
heating the surface soil and thus causing more rapid growth, besides its
direct effect in ripening the fruit. This is well seen in Canada, where,
notwithstanding a six months' winter of extreme severity, vines are
grown as bushes in the open ground, and produce fruit equal to that of
our ordinary greenhouses. Some years back one of our gardening
periodicals obtained from gardeners of forty or fifty years' experience
a body of facts clearly indicating a comparatively recent change of
climate. It was stated that in many parts of the country, especially in
the north, fruits were formerly grown successfully and of good quality
in gardens where they cannot be grown now; and this occurred in places
sufficiently removed from manufacturing centres to be unaffected by any
direct deleterious influence of smoke.
Pages:
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515