212 
PROTECTION FROM HAIL. 
be overlooked. Speaking generally, the best time for the opera¬ 
tion is when the subjects are just commencing their seasonal 
growth, which, of course, will vary with the nature of the plant; 
and the next best is immediately before the cessation of action 
at the close of the season. That grafting should be performed 
at the latter period with success is a strong argument in favour 
of the descent of sap ; and as giving increased force to this view 
of the matter, it has been observed that such as have a mass of 
foliage above the point of contact attach themselves more readily, 
at this period, than those which are destitute of leaves. The 
importance of vegetable physiology to the science of horticulture 
is here again placed in a prominent point of view; and the be¬ 
nefit of its study, to all who desire to pursue the latter in a 
manner apart from mere empirical rules, becomes more and more 
apparent the farther we enter into the question ; and we fervently 
hope for the time when the leading principles of this wide- 
spreading subject shall become established in men’s minds, and 
their practice clearly deduced from its unerring guidance. 
Editor. 
PROTECTION TO PLANT-HOUSES FROM HAIL. 
It may not be amiss, now that this subject is so painfully 
present to the minds of so many whom it concerns, to call atten¬ 
tion to some means of meeting and preventing a repetition of the 
calamity which has overtaken the horticulturists in the vicinity 
of the metropolis within the past month. The newspapers will 
have made our readers aware that since our last a terrific storm 
of thunder, accompanied with by far the most destructive fall of 
hail that we have any record of, visited the central portion of the 
kingdom, dealing desolation and ruin throughout the suburban 
districts of London, to an extent really dreadful to think of. The 
destruction of property among the nurserymen and commercial 
growers in the neighbourhood of Clapham, Brixton, and Vaux- 
hall alone, has been estimated at 18,000/. The amount of capital 
which will thus be withdrawn from trade, to meet the necessary 
repairs, must cause a check to gardening which will extend, like 
