744 
THE TROPICAL AGRICULTURIST. [February i, 1882. 
Our Water Power. — Said Sir W. Thomson, at a 
meeting of the British Association : — Taking Niagara 
as an example, and with the idea of bringing its energy 
usefully to Montreal, Boston, New York, and Phila- 
delphia, I calculated the formula for a distance of 300 
British statute miles (which is greater than the distance 
of any of those four cities from Niagara, and is the 
radius of a circle covering a large, and very important 
'part of the United States and British North America), 
I found almost to my surprize that even with so great 
a distance to be provided for, the conditions are 
thoroughly practicable with good economy, all aspects 
of the case carefully considered. The formula itself 
will be the subject of a technical communication to 
Section A in the course of the meeting on which we 
are now- entering. I therefore at present restrict 
myself to a slight statement of results. 1. Apply 
dynamos driven by Niagara to produce a difference of 
potential of 80,000 volts between a good earth-connex- 
ion and the near end of a solid copper wire of half an 
inch (127 centimetres) diameter, and 300 statute miles 
(483 kilometres) length. 2. Let resistance by driven 
dynamos doing work, or by electric lights, or, as 1 
can now say, by a Faure battery taking in a charge, 
be applied to keep the remote end of a potential 
differing by 64,000 volts from a good earth-plate there. 
3. The result will be a current of 240 webers through 
the wire taking energy from the Niagara end at the 
rate of 26,250-horse power, losing 5,250 (or 20 per cent.) 
of this by the generation and dissipation of heat 
through the conductor and 21 OOO horse power (or 80 
per cent, of the whole) on the recipients at the far 
end. 4. The elevation of temperature above the 
surrounding atmosphere, to allow the heat generated 
in it to escape by radiation and be carried away by 
convection is only about 20degs. centigrade : the wire 
being hung freely exposed to air like on ordinary 
telegraph wire supported on posts. 5. The striking 
distance between flat metallic surfaces with difference 
of potentials or 80,000 volts (or 5,000 Daniells) is 
(Thomson's "Electrostatics and Magnetism," § 340) 
only 18 miillimetres, and therefore there is no diffi- 
culty about the insulation. 6. The cost of the copper 
wire, reckoned at 8d. per lb., is £39,000 ; the interest 
on widen at 5 per cent, is £1,900 a year. If 5,250- 
horse power at the Niagara end costs more than 
£1,900 a year, it wpuld be better economy to put more 
copper into the conductor ; if less, less. I say no 
more on this point at present, as the economy of 
copper for electric conduction will be the subject of 
special communication to the section. I shall only 
say, in .conclusion, that one great difficulty in the way 
of economizing the electrical transmitting power to 
great distances (or even to moderate distances of a few 
kilometres) is now overcome by Paure's splendid in- 
vention. High potential, as Siemens, I believe, first 
pointed out, is the essential for good dynamical eco- 
nony in the electric transmission of power. But what 
are we to do with 80,000 volts when we have them 
at the civilized end of the wire? Imagine a domestic ser- 
vant going to dust air electric lamp with 80,000 volts on 
one of its metals ! Nothing above 200 volts ought on 
any account ever to be admitted into a house or ship 
or place where safeguards against aceident cannot be 
made absolutely and for ever trustworthy against all 
possibility of accident. In an electric workshop 80, 000 
is no more dangerous than a circular saw. Till I learned 
Paure's inventions I could' but think of step-clown 
dynamos, at a main receiving station, to take the 
energj direct from the electric main with its 80,000 
volts, and supply it by secondary 200 volt dynamos 
oi 100-volt dynamos, through proper distributing wires, 
to the bouses and factories and shops where it is to 
he used tor electric lighting, and sewing machines, and 
lathes, and lifts, or whatever other mechanism, wants 
driving power. Now the thing is to be done much 
I more economically, I hope, and certainly with greater 
1 simplicity and regularity by keeping a Faure battery 
of 40,000 cells always being charged from the electric 
main, and applying a me 1 hodical system of removing 
sets of 50, and placing them on the town supply cir- 
cuits, while other sets of 50 are being regularly intro- 
duced into the great bat tery that is being charged, so as 
to keep its number always within 50 of the proper num- 
ber, which would be about 40,000, if the potential the 
emitting end ofthemainis 80,000 volts. 
Ceylon Tea. in London. — We call attention to 
the full report of the recent sale of Ceylon tea 
in Loudon, furnished by Messrs. Hutchison & Co. 
The highest price realized, Is 7d, was for Broken 
Pekoe with Mr. Elphinstone's mark. Improvement 
in manufacture is still the desideratum. 
Tea. — The Indian Echo is the name of the organ of the 
"Indian Tea Direct Supply Association" recently 
established in London. The paper in question is 
publisi ed in the interests, apparently, of one Tea 
Association only, but doubtless the experiment will be 
adopted not only by Ceylon tea grower's agents, but by 
those interested in the older staple, coffee. — Madras Mail. 
Willow Leaves as a Cure for Fever.— The De- 
cember number of the Indian Medical Gazette contains 
a paper by Asst. Surgeon Chetan Shah on the use of wil- 
low leaves in intermittent fever. As the writer says, 
the remedy is not a new one, nor can its efficacy be com- 
pared to that of quinine or strychnia, but amongst 
natives, especially females, quinine often causes great 
irritation of the alimentary canal and induces dysentery : 
in such cases the juice of fresh willow leaves diluted 
with water proved very successful. Where willows did 
not exist narcotine was found to answer the purpose. 
Lower Dikoya, 17th Jan. — Nothing could be finer 
than the weather. So far, the rains in December no 
doubt encouraged a light attack of leaf-disease, which 
we would not otherwise have had, but the good done 
to coffee was far more by the one than the hnrm by the 
other. January is as it should be— hot, dry days and 
cold nights. A good blossom is appearing in the bud, 
but it will take a month's or six weeks' drought to 
check growth sufficiently to bring out a large general 
blossom. And I think the trees are in a better state 
to bear than they have been for some years. All de- 
pends on the weather for the next three months. No 
in is required before the end of February. It is too 
early even to guess at what next year may be. ' How- 
ever, it promises to be favourable. 
Ostrich Farming~in Mauritius. — We received an inter- 
esting addition to our zoology by the " Day Dawn " from 
the Cape, viz., five full-grown ostriches. I believe that 
several more were shipped, which, however, linf ortunately 
died on the voyage. These birds were put up at auction ; but 
didnot realize more than the following prices, which, I am 
afraid, will not encourage further shipments of this stock to 
our island: — 1 male ... ... R320 
«'•' •'■ 1 „ 310 
1 „ ... - ... 290 
1 „ ... ... 274 
1 female ... ... 810 
The principal buyer was Mr. A. Colin, who intends to 
follow the example of another of our large landed-pro- 
prietors and establish an ostrich farm on one of his estates. 
The French Imperial Government has presented to that 
of the neighbouring French Colony of Reunion the cost 
of two very important undertakings, with a view to 
give an impetus to trade in that colony, viz. first that 
of the railway encircling the island, the amount expended 
on which has amounted to about a million sterling ; and 
secondly, that of a harbour, the cost of which is estim- 
ated (for it is not yet finished) at 40 millions of francs. 
These enterprizes, when completed, will undoubtedly give 
a great impulse to trade there. According to the circular 
of Messrs. L. Aubert & Co. of Reunion, sugar is selling 
there still at the comparatively low price of Fes. 21'50 
for quality indicating 88° or No. 12 Dutch Standard. — 
'Mauritius ( 'orrespowEent, 
