THE TROPICAL A^tJISLTURlST. 
[January i, 1891. 
500 
PURE CEYLON TEAS FN. IMPURE TEA 
BINS AND “ CLEANSING FIRES.” 
That the second is incompatible with the first goes 
without saying. Then how to keep the second con- 
stantly pure and without much trouble is the question. 
Mr. John Hughes, the Chemist, has already told us 
how to purify metal tea-pots— clean them well out 
with hot water and while the moisture still clings 
to their interior drop in a live coal and close the 
lid— the resultant steam will, in five minutes, thoroughly 
cleanse metal te.a-pot. Carry the same idea out with 
regard to tea bins. Speedily sponge down the aides, 
then rapidly place on two bricks at the bottom a 
piece of iron, the size of half a brick, brought to 
white heat in the Sirocco, close down the lid and 
make aiitight, and the virtue of “ cleansing fires” 
is at once secured. — Cor, 
THUNDERSTORM S. 
Robekt H. Scoti, in “Longman’s Magazine.” 
A flash of lightning a mile in length is nothing 
very extraordinary, and it is therefore not to be 
wondered at that experiments to bring electricity 
down from the clouds are very dangerous, and 
have frequently had fatal results. Soon after 
Franklin, in the last century, had made his famous 
experiment with a kite, and proved that electricity 
existed in a thunder-cloud, natural philosophers 
generally began to imitate him. One of them in 
St. Petersburg, a Professor Eiohmann, arranged in 
apparatus to collect this electricity. On the first 
ocoasion of a storm he went to his laboratory to 
observe the effects. A ball of fire was seen to 
leap from the apparatus to his head, and he fell 
lifeless. Having thus got some idea of_ the force 
exerted by lightning, it may be interesting to the 
reader to learn something as to the means we possess 
of guarding ourselves, or rather our houses, from 
injury. A flash of lightning really consists of a 
discharge between two objects, say two clouds, or 
a, cloud and the earth, oppositely electrified, the 
charges on which suddenly combine, with the 
manifestation of light and heat. Lightning con- 
ductors are ocntrivances by which the electricity 
of the earth is allowed to escape quietly into the 
atmosphere, where it meets with electricity of the 
opposite character from the clouds, and the two 
neutralise each other quietly, without any explosive 
discharge, or, in other words, without lightning. 
I need not go back to the first principles of 
electrical science and explain why it is that electri- 
city passes most easily through metals, and escapes 
with greater freedom from sharp points than from 
rounded knobs. Assuming these elementary facts, 
I may say that on any object, such as a he use 
or other building, the electricity tends to accumulate 
itself on all projecting portions of the roof, &c,, 
and especially on the highest points of it. 
The ideal complete lightning-rod system would 
call for a sharp. pointed copper rod erected at each 
of these projecting pir.nacles, and rising above it, 
and would then connect all of these separate points 
by copper rods, and eventually carry down a stout 
copper rod to the earth. Care must be taken that 
due attention is paid to certain main precautions;— 
( 1 ) The point of the conductor must be kept sharp; 
(2> the section of the conducting-rod mutt be 
sufficient to allow the electricity to piss along it ; 
(3) the rod must be perfectly continuous ; and_ lastly 
(4) , the rod must bn eflioiently connected with the 
ground. 1. The sharpness of the point is insured 
by gilding it or coating it with some metal which 
reeiata oxidation. 2. As to the sootion of the rod, 
tkbat half an inch ip diameter is swllioient for 
all ordinary buildings. Bars are not usually em- 
ployed, as it is difficult to bend them over cornices, 
&c. ; accordingly, either wire ropes or tapes are 
taken. The wire ropes are more liable to corrosion 
from wet getting in between the strands than are 
tapes, so that the latter are generally preferred. 
The metal used is always copper, bemg less 
oxidisable than iron, and being reasonably cheap 
and a very good conductor. 3. The continuity of 
the metallic connection from the highest point of 
the rod to the ground can only be secured by 
having as few joints as may be, and by making 
those joints as true and firm as possible by soldering. 
The joints should be examined from time to time, 
for it is often found, on examination of old con- 
ductors, that while the copper wire or tape is 
quite sound along its straight reaches, at the bends 
or joints corrosion has set in. As a chain is no 
stronger than its weakest link, a corroded conductor, 
such as has been described, is perfectly useless. 
4. The earth connection. — It is not easy in all 
cases to insure that this is satisfactory. Electri- 
city will not pass at all so easily into dry earth 
as into wet earth, and merely plunging the end 
of the rope or tape into wet earth is not .tUfficient, 
The conductor from the building should be soldered 
at its end to a large sheet of copper, say at least 
two square yards in area, buried in damp soil, 
or else soldered to the water or gas mains, so as to 
insure that a large surface of metal is in contact 
with damp earth. 
Supposing that the whole system of protection 
against damage from lig’otning has been properly 
planned, the work should be carefully tested after 
its completion, because injury to it often occurs 
at the vei'y last, owing to accidental causes, or to 
the carelessness of workmen. Conductors should 
also be examined from time to time, throughout 
their whole length, to make sure that all the joints 
are sound. Care should also be taken that the 
earth in which the terminating plate is buried is 
kept thoroughly moist. If any of these particulars 
be neglected, the conductor will be practically use- 
less, and will afford no protection to the structure. 
The extreme practical importance of security against 
lightning must be my excuse for having been more 
diffuse over the object of lightning-conductors than 
over other details of the phenomena and eSeets of 
thunderstorms . — Puhlic Opinion. 
4 
INDIAN TEA IN PARIS. 
All who are interested in the progress of the tea 
induttry in India will be pleased to hear of efforts 
being made to open new markets for the yearly in- 
creasing production of the country. The Indian tea 
planters too long- neglected this work, bnt during the 
last few years they have been striving to make up 
lost ground. By far the most interesting and im- 
portant of these undertakings is that which is beifig 
conducted in Paris. Paris is important as being not 
only the capital of France, but the centre of the world 
of fashion, although, in the interests of British tea- 
growers, we must regret that up to the present fashion 
has not set in favour of tea. 
Under the auspices of this movement one of the 
first tea cafes in Paris has been opened at 12, Hue 
Auber, centrally situated near the Opera House, and 
it is certain that it will be a boon to those who love 
good tea, well made and served. In order to associate 
this new departure with the Indian Palace, the designs 
have been prepared by the same architect, Mr. Purdon 
Olaike, C.I.E., f.eib.a., who is probably better 
qualified than any other man in Europe to show 
what can be done in the adaptation of Indian 
architecture to European requirements. The facade, 
au iiroade of three entranoes, is in the Mogul 
