1372. ] 
GARDEN GOSSIP. 
119 
but over all vacant ground, to keep down weeds. Clean and roll the gravel 
walks.—M. Saul, Stourton. 
GARDEN GOSSIP. 
ENERAL Pleasanton, of Philadelphia, is reported to have grown some 
extraordinary Grapes under violet-coloured glass. Attempts have been 
made to explain his success, by the supposition that the violet glass which 
hff he used had a concentrating effect upon the more chemically active rays 
contained in ordinary light. Professor Thisolton Dyer, however, recently pointed out that 
what was done in passing white light through coloured glass was to subtract from, not add to 
it. As regards the formation of leaf-green in plants, and the evolution of oxygen from their 
foliage, it was the red and yellow rays, rather than the violet, which were most effective. 
Violet light was anything but advantageous to two of the things that were most essential in 
plant growth. This was a rather unexpected result, because it was the most refrangible or 
violet rays in light which had the greatest chemical effect, as for example, in photography. 
But in any case violet glass could only part the violet rays from the red ; it could not add to 
their effect. The upshot of our knowledge about the subject w r as far from calculated to 
encourage the adoption of General Pleasanton’s system. The green colouration of leaves, as 
every one knew, required the influence of solar energy to accomplish the deoxidation essential 
to its development. The tints of flowers, on the other hand, were rather results of oxidation 
—were, indeed, in a sense, products of combustion, and hence could, to a great extent, be 
developed apart from the influence of light. A blue Hyacinth had developed its colour in a 
perfectly dark wine-cellar. A red Hyacinth had, however, been bleached by this treatment, 
and it was well known also that the white Lilac of Parisian florists was the coloured variety 
grown under peculiar conditions with a very limited supply of light. Probably in these cases 
light was necessary to promote the oxidation which produced the colouration. 
— m- D. T. Fish’s remarks on Hard Soil for Boses are valuable and 
well-put. In planting Dog-roses for stocks it is customary in tlie nurseries, even 
wlien tke soil is strong, to tread tliem as firmly as possible. Tlie finest of 
Climbing Boses I ever saw was composed of Ayrshire, Sempervirens, and Multiflora, the 
ground beneath a paved north border on which Alpines in pots were set, with a hard gravel walk 
beyond. The roses received water in dry summer weather by the "watering of the Alpines. Once, 
when digging for gravel, I removed some Sempervirens Roses and cleared away two feet of the 
surface soil. Some of the roots of the roses were left behind in the gravel, and these shot up 
with extraordinary vigour, quickly forming large bushy plants. Here was a hint from 
nature. Why should not roses be propagated from roots?— William Paul. 
- According to Mr. G-. D. Brumliam, the Coming Summer will be a hot 
one. The laws on which this opinion is based are these :—1. When the mean 
temperature of the period from the middle of February to the middle of March is 
very high (about 44°-5), the following summer is always very hot. The only instances of 
such a high mean temperature at Greenwich occurred in the following years, viz.:—1826 
(44°-S), 1834 (45°-8), 1846 (46°*3), 1859 (46°*3), and 1868 (44°-7), and all these years were 
remarkably hot. This year the mean temperature of the period referred to was 45°-5. When 
the mean temperature of the period referred to is even a slight fraction below 44°, a warm 
summer follows; such was the case in 1822, 1849, 1850, and 1861. 2. When the rainfall 
is very slight in October or November (not more than 0-8 inch) the succeeding summer is 
always very hot. The following are all the instances that have occurred at Greenwich relative to 
this law since rainfall registration was commenced there:—October, 1830 ((0-8 inch) ; October, 
1834 (0-4); November, 1851 (0-6); November, 1858 (0-5); November, 1867 (0*4); and 
November, 1872 (0-5). The following summers of 1831, 1835, 1852, 1859, and 1868 were 
very hot; therefore, according to this law, the coming summer must be hot. As a very low 
barometrical mean in the first three months of the year indicates considerable rain for the 
summer, it appears that the coming season will have a rainfall abovo the average, notwith¬ 
standing several periods of dry weather. 
- 3£n reference to the Cultivation of Gerardias , Mr. E. S. Rand, wko 
is weT known amongst American horticulturists, points out, as regards the 
