36 o 
THE TROPICAL AORtCULTUmST. 
[November r, 1890. 
test. If We. carefully exclude the eives from moisture’ 
the plants die, however much water may be applied 
to the roots. The rcols are particularly dense in 
texture; the leaves offer a large surface, covered with 
innumerable little hairs for the retention of moisture, 
and mouths (ur stomata) for its absorption. A great 
variety of trees and plants fiouri.sh in the most arid, 
saudy, and stony soil. If we examine sap, wo find that 
in the leaves arul upper twigs aud branches it is almost 
perfectly limpid; it grows dense as it reaches the 
roots. The maple trees give a plen'iful supply - f 
water iu the upper part, but the th'ck syrupy fluid 
from which sugar is obtained can only be tapped near 
the roots. All thi- go. s far to show that the waUr, 
the principal constituent of sap, is taken in by the 
leaves ano sent down to the roots; it grows thick as 
it descends by being expo.'ed to the chemical influence 
of the rising gases. But it is not only water thi is 
taken in by the leaves. The mineral consiituents of 
the treo-blo d also seems to be derived from the air 
and not from the soil*. Independent exporiiuents on a 
wide scale have clearly demo- strated that our atino- 
sphare is heavily charged with organic matter, dead 
and jiving, in oivanic atoms — the beams which we see 
in the .suulight-i’ays of a darkened room. Blr. J h-i 
Aitkin found hat the dust particles in the afmo.sph-re 
of Cannes fluctuated be'ween 1,5*10 and 140,000 per 
cubic centimi re. At the top of the Eiffel Tower 
104,000 panicles weie found to the cubic centimetre; 
but this fell to less than 23 000 after heavy raiu, EO 
that clearly the rain had washed the atmosph re, and 
taken tie organic and iuorg.mic atoms to thevegtti- 
tion b- low. At all events the ajr contains abuudance 
of mineral and otb^r so id foo I f-tr piants; and wdieu 
we find the le»ves o>mtauiiug more mineral matter and 
greater c dour than the roots, it seems hard to be’ieve 
that our teachers have been over accurate iii instilling 
into us the theory of risiog sap. 
Now, as to the gase.s. We must acknowledge that 
gases are plentiful enough in the air, but it is beyond 
dispute that those found necessary for the life and 
growth of plants are most richly elaborated in the sod. 
Plants with very deep roots a'6 rarely fruitful. We 
kn w that soil dug up from great depths is practically 
dead, and wi 1 not aff.ir.i a habita'ton for plants. 
Earth for successful plant growing mu.tt be irap eg- 
nated with . organic matter capable of decay, and 
cjnsequeutly of evolving gas. This is an important 
point from ihe economic as well as the biological pcint 
of view. Fruit tre^s are found to prosper best and 
give the largest crops when their roots are near the 
surface of the toil. Indeed, some of the grandest 
orchards are'pir i-rlly paved at a depth of a few feet 
fronr the surface with large stones or hard pres'ed 
debris, which forces the fruit trees to spread their 
roots near the surface of the soil, where the dectm- 
position of natural vegetable refuse and artificially 
applied manures are in the most active state of decom- 
IJOsition, and consequently in soil richly impregnated 
with ga<es. Roots, while ill-suited for absorbing water, 
can easily taka up ga'es. We find the roots 
comparatively free from colouring matt,, r and dry, 
the sap being thick. The gases in rising act 
chemically upon the sap, the water and its organic 
and inorganic consiituents, and finally escape through 
the leaves, and even the bark. That a very large 
amount of eas is given off by le-sves, flowers, etc,, is an 
undeniable fact. We crush a leaf or twig betwoeu our 
fingers and obtain a more or less pleasant odour, and 
that this is due to gases can be easily proved, for many 
aromatic plants will soon ch.irge the atmosphere of a 
closed room uncomfortable, some'imes even dangerously, 
with compounds of oxygen, liy irogen aud nitrogen, 
some of which .are ]iro' ably alkuloia'a! in character. 
Indeed, to such a large extent is thi.s the case with 
ceriaiii plants tint the natural escape of gas from the 
rue plant on hot, still nights can be actua'ly set on 
fire. 
All til's, it may bo said, is very interesting, but 
what practical lesson does it teach us ? The great 
• This is very do . ibtfu', as the mineral portion comes 
from the soil more likely — J. II, 
practical lesson is this — theletfis the most important- 
part of the tree. If the plant procures its liquid aud 
solid material for life and growth from the leaf, theu 
clearly it is a mistake to be coutinuilly lopping 
and pruning, for by f-dlowing this practice we reduce 
the assjmilatiug powers of the plants. This seems to 
be proved by the f ^ct that heavily pruned trees are 
cotpstintly throwing out sucke s and shoots — in rea'ity 
endeavouring to ex'e d their foliage in order to com- 
pensate for their mutilation. Cultivated trees that 
are pruned and deprive I of their life-giving foliage 
decrease iu str. ngth, and fall easier victims t a disease 
than the ;heaviiy-fol aged trees in the'r i.atural state. 
If, therefore, we are to accept the descending sap 
theory, we shall have to spare the upper branches and 
cherish the leaves. Again if the sap, the water with its 
org.inic and inorganic matter, comes from thn air, aud 
the gases from the soil, then the reo-'gnition of such 
facte would have an undoubted influence upon our 
present method.s of agriculture, depei.ding upon 
arb’tiary theori-^s of soil exhau-stion audrot.tion of 
crops. Agriculture will be as much a .science a - ever, 
but a more remunerative one, and 'ur f-conoraic-i of the 
soil will have to undergo some modification. — Globe. 
♦ 
P.’PDY, which forms the principal monsoon crop in 
the Madras Presidency, has this year been planted 
over an area of 1,272,100 acres, which is a P' le 
under the normal area. Gingelly, which ccin -s 
next in importance, shows a slight decrease as 
compared with last year, but the most marked 
falling off is in indigo which has decreased from 
191,900, to 114,200 acres. The cause of tiiis is said 
to lie tho fall in the price of indigo, and also the 
late and insufficient rains. The repot Is from various 
districts show ihat the rains have, on the whole, been 
favourable. Cotton is cultivated over about 70,000 
acre?, but reports on the condition of this crop have 
not yet been received . — Indian Agriculturist. 
Nutmeg Culture in Ceylon. — We call atten- 
tion to the letter of “ W, D. G.” further on on 
this subject. We do not expect that Ceylon will 
ever be the scene of any great extent of nutmeg, any 
more than of cacao cultivation, and for the same 
reason, the absence of good de“p rich soil save in 
exceptional ‘‘ pockets.” But wherever the soil and 
olimata are suitable and the nutmeg is found to 
grow, we certainly think that special attention 
should be given to it, even though the p'anter may 
feel that his children or posterity, rather than 
himself, are to reap the benefit. The lowest of 
“W.D G.’s” estimates or returns — or E200 per 
acre— is so good as to encourage not a few to run 
after nutmeg cultivation. 
Forestry in Bengal. — The Bengal Forest Depart- 
ment is a flourishing branch of the administration 
to judge from the financial results, which show a 
net profit for the last official year amounting to 
over lakhs of riiposs. The profit is very great 
in the Sunderbuns Division, from which Calcutta 
is supplied with fuel, as are also the important 
sugar and other works scattered through Khulna 
and Jessora. The Lieutenant-Governor is in favour 
of strengthening establishments a.s much as possible 
in this division, and of making free use of steam 
launches for inspection, it being generally believed 
that the revenue here is capable of much greater 
expansion. It is also desirable (His Honor con- 
siders) to free more officers for mAking working 
plans~a duty too generally neglected, and this 
can only bo accomplished by reducing establishments 
where they do not pay, namely, in Ghota Nagpore 
and Orissa. In the. latter province work will 
probably be considerably reduced when the forest 
boundaries have been re-aligned by the exclusion 
of village grazing and fuel grounds — a measure to 
which the Lieutenant Governor attaches great 
importance in the interests of the cultivators. — 
Fioneer, Oct, 7th. 
