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CULTURE OF THE MANGO. 
hard, unwrought earth close to it, shall be free from any particle of rime, unless 
where some stray weed, projecting point, or piece of chalk, and the like, may project 
from the surface ? Let us admit that these substances become dewed by the agency 
of radiation. Yet, what then ? Is radiation anything more than an effect produced 
by that active cause which governs every phenomenon of attraction and repulsion ? 
If vegetables be, in fact, vehicles for electric currents — if the flow and direction of 
their vital and secreted fluids be caused by the influence of those currents, then may 
we philosophically infer that the radiating power of plants, and their covering dew, 
must depend upon the instrumentality of that agent which is ever present in the 
atmosphere, can be detected and measured by our instruments, and is known to 
induce those meteoric changes that are in perpetual operation throughout the aerial 
ocean. 
We know that atmospheric moisture is maintained in a state of vapour by a 
repulsive power. Electricity — or call it ethereal elementary fire — exists in two 
states, plus and minus — positive and negative ; each condition or axis of power being 
repulsive of itself, but exerting attraction on particles of an opposite power. The 
moisture of the atmosphere may be either positive or negative, and, in either case, it 
exerts, by induction, an opposite condition on all bodies within the sphere of its 
influence. We are ignorant of prime causes — what electricity is we know not ; but 
yet, philosophers have been enabled to appreciate some of its laws. 
Whenever, therefore, the electrised vapours meet with a series of vegetable points 
in an opposite state of electricity, the two conditions must act upon and neutralise 
each other, and cause the deposition of those aqueous particles, which, till then, had 
been held in a state of repulsion, and of infinitely minute division. 
If these views be correct — and as yet they have not been shown to be unphilo- 
sophical — the deposition of the dew may be considered an electrical phenomenon, 
CULTURE OF THE MANGO. 
The Mango, Mangifera indica of our Botanical Catalogues is the Mangifera 
Amba of Forsk. Descrip. 205 ; and the Mangifera domestica of Gsert., Fr. It is a 
native of the East Indies, whence it was introduced* in 1690, and is associated with 
the Natural Order Terebinthacea, because of the turpentine flavour which most of 
these plants possess. 
In its native country it forms a tall spreading tree, in shape not much unlike a 
Walnut-tree, but when in flower it might, at a distance, be mistaken for a Spanish 
Chestnut. The ivood is brown and inferior. The leaves are entire, feather- 
nerved, oblong-lanceolate, stalked, seven or eight inches long, and two or more 
broad, of a fine strong green, and growing in bunches at the extremities of the 
branches. Flowers in loose, terminal, erect panicles, polygamous. Calyx five- 
