August, 30, 1883. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
193 
The sap, after elaboration in these organs, differs in every plant, though, 
as far as experiments have been tried, it appears to be nearly the same 
in all vegetables when it first arrives to them. The power of a leaf to 
generate sap is in proportion to its area of surface, exposure to the light, 
and congenial situation. 
Leaves throw off a very considerable quantity of water. Dr. Hales 
found that a Cabbage emitted daily nearly half its weight of moisture ; 
a Sunflower, 3 feet high, perspired 1 lb. If ozs.; and Spearmint exhales 
times its weight in the same period. But of all the plants, the diurnal 
perspiration of which has been ascertained, the Cornelian Cherry (Cornus 
inascula) transpires the most, the exhalation amounting to nearly twice 
the weight of the plant in twenty-four hours. This aqueous expiration 
takes place chiefly during the day, is much promoted by heat, and checked 
by rain or a reduction of temperature. On the free performance of this 
function of plants their health is dependent in a very high degree, and 
we believe that half the epidemics to which they are subject arise from 
its derangement. 
Evergreens transpire less moisture than deciduous plants, which 
would lead to the expectation that they are more capable of living in 
dry situations, which in general is really the case. 
The matter transpired by a healthy plant is nearly pure water, 
5000 grains of it never containing more than one grain of solid matter, 
and this is constituted of resinous and gummy matter, with carbonate 
and sulphate of lime. It appears to be nearly the same in all plants. 
The quantity, however, varies in every species, probably in every 
individual—and is greatly influenced by the quantity of water applied 
to the roots. Under precisely similar circumstances Sennebier obtained 
the following results :— 
Grs. Grs. 
A Peach branch, imbibing 100 exhaled 35 
>♦ ,,210 „ 90 
„ ,, 220 ft 120 
,, ,, 1 10 f f 295 
We have found the branch of a Pelargonium, that, whilst growing on 
the parent stem, exhaled only twenty grains in twenty-four hours, more 
than trebled that quantity in the same time when cut from the stem and 
placed with the divided end in water. This increased transpiration is 
attended by a proportionate reduction of temperature ; for a collection 
of Pelargoniums, in the midst of which Fahrenheit’s thermometer stood 
at 55° fell to 48° within two hours after a plentiful watering to their roots 
only, though the water was of the same temperature as the greenhouse. 
For the purpose of ascertaining the composition of the liquid transpired 
by plants, M. Sennebier collected 13,030 grains of it from a Pine during 
the months of May and June. When evaporated 2 grains of residuum 
were left, composed of nearly ^ grain of carbonate of lime (chalk), l-12th 
grain of sulphate of lime (gypsum). 4 grain of matter apparently gum, 
and ^ grain apparently resinous. He analysed 00,768 grains of a similar 
liquid collected from the Vine during July and August. The residuum 
after evaporation weighed 2£ grains, composed of J grain of carbonate 
of lime, j grain of sulphate of lime, £ grain of gum, and i grain of resin. 
The liquid transpired by Aster Novae-Anglim afforded precisely the same 
ingredients.— (Encyc. Metlt. Plnjs. Vcget., 287.) 
As the season of growth advances the trauspiring power of leaves 
decreases. Under similar circumstances Sennebier found the transpiration 
much greater in May than in September. 
The transpiration of plants decreases with that of the temperature 
to which they are exposed as well as with the period of their growth. 
This explains why the gardener finds that his plants do not require so 
much water in cold weather, nor during the time that elapses between 
the fall of their blossom and the ripening of their seed. During this 
period they do not transpire more than one-half so much as during the 
period preceding and attending upon their blooming. 
The transpiration takes place from the upper surfaces of the leaves, 
and if these surfaces are coated with varnish the leaves gradually decay 
and fall, and the growth of the plant ceases until fresh leaves are pro¬ 
duced ; hence arises the benefit which plants derive in rooms, green¬ 
houses, and other confined enclosures from keepiug those surfaces cleansed 
with the sponge and syringe. The advantage derived by plants from 
having their leaves cleansed was exemplified by the following ex¬ 
periment : — 
Two Orange trees, weighing respectively 18 ozs. and 20 ozs., were 
allow'ed to vegetate without their leaves beiDg cleansed for a whole 
twelvemonth ; and two others, weighing 19 ozs. and 20g- ozs. each, had 
their leaves sponged with tepid water once a week. The two first in¬ 
creased in weight less than half an ounce each, whilst of the two latter 
■one had increased 2 and the other nearly 3 ozs. In all other respects 
they had been treated similarly. 
It must be remembered, however, in using the sponge and the 
syringe that the under side of the leaves is an absorbing surface, bene¬ 
fited by being kept clean and by the application of moisture. The 
Kidney Bean, Sunflower, Cabbage, and Spinach absorb moisture equally 
by their under and upper surfaces ; the Cockscomb, purple-leaved Ama¬ 
ranth, Heliotrope, Lilac, and Balm absorb most freely by their upper 
surfaces ; and the Vine, Pear, Cherry, Apricot, Walnut, Mulberry, and 
Rose absorb most by their under surfaces.—J. 
MADRAS AND ITS VEGETATION. 
The gentleman who was deputed from India to report on the forests 
of Ceylon thus gives his impressions of Madras in the Indian Forester :— 
There can be no doubt that Madras is in process of becoming one of 
the handsomest towns in India. Were it not for its great area and want 
of local municipal funds it would long ago have been undoubtedly one 
of the finest as it is one of the healthiest of them. A great feature in 
Madras is the number of large buildings, mostly public, built in the 
oriental style of architecture. Most prominent of all these is the Chepauk 
Palace, an old palace of the Nawabs of the Carnatic, largely added to 
and now used by the Board of Revenue. Here I found the Forest office, 
with a fine verandah looking out to sea over a pretty grass lawn adorned 
with fountains and young Poon trees. Near it is the grand new Uni¬ 
versity Senate house, which seems to the uninitiated to be a mixture of 
Gothic and Saracenic architecture. Behind these and other neighbour¬ 
ing large buildings are the grounds of Government Bouse, in process of 
transformation into a botanic garden, and a very pretty garden it will 
be when completed, for besides the sea frontage and the broad mouth of 
the Coom river, there are large tanks and the Buckingham Canal, pretty 
bridges and groups of trees of various kinds. The summer avenue trees 
of Madras are the Nim, the Casuarina, and the Odina Wodier, the latter 
most remarkable, as Dr. Brandis has pointed out, for retaining its leaves 
the whole year round, while only a few miles into the country it may be 
found in its usual cold-weather leafless state. Hedges, principally of 
Inga dulcis, surround the large compounds of the houses, while in places 
groves of Cocoa-nut Palms remind us of the first impressions of India 
we gained on landing in Ceylon. A special feature in Madras, and most 
of all in the more aristocratic quarters of Nangumbaukum, Chetptu, 
Egmore, and Adyar, is the immense size of the house compounds. Some 
of them would make a not inconsiderable park for an English squire, and 
the houses are generally large, airy, and comfortable. The gardens seem 
to keep themselves. Ferns, and especially Adianta, thrive most luxuri¬ 
antly in the shade, while the magnificent growth of Crotons, which in 
Calcutta one is chiefly accustomed to see carefully tended in small pots, 
is in Madras a most striking feature, and makes gay the lawns and 
shrubberies with every shade of red and yellow and orange and purple. 
Here they are not small plants in small pots, but, either in the ground 
direct or in huge pots, they show tall masses of column often 10 to 15 feet 
high and proportionately broad. The great number of Nim trees is very 
noticeable, while the yellow pods of Albizzia Lebbek keep up their cease¬ 
less rattle at every puff of sea breeze which shakes the roadside trees. 
The public gardens, besides the new one which is being made near 
Government House, are the Peoples’ Park and the Agri-Horticultural. 
The former, near the handsome Madras Railway station, is not very well 
kept, and possesses very few trees of any size, but the latter has, though 
of small area, a particularly fine collection of trees and interesting plants. 
The curious Kigelia pinnata with spreading branches and huge Pumpkin¬ 
like fruits hanging at the end of long strings from the branches attracts 
attention at once, and there is a Baobab which gives a very good idea of 
what a strange object it must be in a Central African landscape. The 
Mahogany seems to thrive, and so do numerous species of Diospyros, 
while among the specimens of Palms are some which I do not remember 
even to have seen in the Palm house or the palmetum at Calcutta. A 
rather longer excursion may be made to Guindy Park, which lies away 
to the west behind the model farm of Sydapet. Guindy Park is the hot- 
weather residence of the Governor, and the shrubberies present speci¬ 
men trees of almost everything curious that can be thought of. But to 
the forester there is nothing so interesting as the Casuarina, and indeed 
I expect that the Madras Presidency can in its coast plantations of 
Casuarina rival the work done on the dunes of Gascony with the Maritime 
Pine. 
WQRKJqrthe WEEK.. 
KITCHEN GARDEN. 
Globa Artichohes .—Under ordinary cultivation the heads are mostly 
too old for use now, and some of them that were not required may have 
been left on the plants. These are no goxi for any purpose, but rather 
injurious, and should all be cut off at once. Most of the stems, too, may 
be cut away close to the soil, and all decayed leaves removed at the 
same time. When this has been done if the soil is very dry the plants 
should receive a thorough watering, afterwards mulching with some 
6hort manure, and then fine healthy crowns will be matured for fruiting 
next year. 
Herbs—A good quantity of the most useful of these should be cut 
and dried before the season advances further. Mint, Sage, and Thyme 
are amongst the principal, and may be cut to within 3 inches or so from 
the base. The best place to dry the tops is an open shed. Sometimes 
they are spread out on the tables and floors, but we often tie them up 
in loose bundles and hang them up to dry. The main thing is to dry 
them so as to retain their colour, and this may be done if they are not 
frizzled in the sun. About this time every season w r e are in the habit of 
sending a quantity of herbs to the cook to be dried for the winter, and 
for some purposes her plan of drying is the best. They are spread out in 
front of a large fire, and after being there for an hour or two they 
become so dry as to be easily powdered. In this state they are placed in 
bottles and firmly corked. There they are kept quite dry, and they 
retain their flavour for a great length of time. Parsley and Celery leaves 
