514 
NATURE 
| March 30, 1882 
extremely simple. It is composed (Fig. 1) of two metallic 
plates, R, R, forming springs, and separated by a small 
piece of fusible metal, S, which is isolated from the plates 
by paper, or any other isolating body. The heat caused by 
the fire melts the metal, and the plates coming into con- 
tact, the electric acts upon the automatic supply-cock. 
This self-acting supply-cock (Fig. 1) is composed of an 
electro-magnet, M, which, under the action of the current, 
becomes active, and attracts the arm N, thus setting free 
the lever, E. The weight, F, then turns from right to left, 
and, after describing the quarter of a circle, falls upon 
the lever, H, whilst the part, G, removes a check which 
has kept the lever, P, in position. Under the action of 
the weight, F, and by means of the lever, P, which has its 
fulcrum in the point, J, the supply-cock, C, is turned, and 
the water rushes into the pipe, A, to be discharged above. 
The cock at B, which is worked by hand, serves to stop 
the supply when the fire is extinguished, or when repairs 
are being made. Under ordinary circumstances, it must 
be always open, else the action of the automatic supply- 
cock would be of no effect. 
The water pouring upwards into the pipes ought to be 
discharged at the point where the fire appears. Ordinary 
perforated pipes may be used, but it is preferable to 
localise the discharge of water by the explosion of gun- 
cotton. This is produced (Fig. 2) either by the inflam- 
mation of very combustible strings K, which set fire 
through D to some gun-cotton placed in the small pistons 
B; or electrically (Fig. 3) by a fine platinum wire N being 
rendered incandescent by the current, and thus exploding 
the gun-cotton. For this purpose the two conducting 
wires O and P are separated by an insulating combustible 
matter and a fusible conductor, resembling those of M. 
Charpentier. The increase of temperature accordingly 
completes the circuit and causes the explosion. When 
there is no public supply of water, as in small towns, M. 
Maxi n would then utilise the electric current as follows :— 
The weight F (Fig. 1) when set free falls on a bottle of 
sulphuric acid placed over a reservoir half filled with 
water, containing a certain proportion of lime. A large 
quantity of carbonic acid being thus produced in a closed 
reservoir, the pressure forces the water inio the systen of 
pipes. Fig. 4, the section of a large theatre, shows how 
the system of pipes may be disposed around the stage. 
Such, substantially, are the principles of M. Maxim’s 
apparatus for preventing fires in theatres and places 
where people assemble in numbers, such as large ware- 
houses, hotels, &c. 
Taking the most impartial view of the advantages to 
be gained by this apparatus, we hope it will soon be sub- 
mitted to the test of experience, while desiring there may 
never be any occasion of making its effectiveness too 
prominent. 
ART METAL WORK OF JAPAN 
FOR centuries past the arti-ts of Japan have earned 
for themselves a reputation for their skill in the 
working of metals, and at the present day their produc- 
tions in bronze, iron and steel, excite admiration and 
astonishment. This art industry is of extreme antiquity. 
Mr. Satow, in his recent handbook of Central and 
Northern Japan, describes tke colossal image of Buddha 
at Nara It was first cast in 749 A.D., and was set up in 
its present position. It suffered from various accidents, 
and in 1567 the temple was burned to the ground, the 
head of the image falling off. It was replaced not long 
afterwards, and we may therefore assign to the body an 
age of 1140 years, and to the head about 300 years, 
Buddha is represented seated cross-legged on a dais which 
is of bronze, and represents the calyx of a lotus. The 
figure is 53} feet high; the face is 16 feet long, and 9} 
wide, while 966 curls adorn the head, around which is a 
halo 78 feet in diameter, on which are images 8 feet in 
length. A roof protects the image, and a staging is 
erected to assist visitors in examining it. The casting is 
said to have been attempted seven times before it was 
accomplished, and 3000 tons of charcoal were used in the 
operation. The whole is said to weigh 450 tons, and the 
alloy is composed of :— 
Gold 500 Ibs. 
Mercury 1,954 »5 
Tin 16,827 ,, 
Copper 986,080 ,, 
‘The body of the image and all the most ancient part 
of the lotus flowers on which it is seated are apparently 
formed of plates of bronze to inches by 12, soldered 
together, except the modern parts, which are much larger 
castings. A peculiar method of construction is said to 
have been adopted, namely, of gradually building up the 
walls of the mould as the lower part of the casting 
cooled, instead of constructing the whole mould first, and 
then making the casting in a single piece.’’ The other 
large image of Dai Butsu at Kamakura, near Yokohama, 
is somewhat smaller than this, and dates from a period 
three centuries more recent. The various temple bells, 
some of which are of great size, are remarkable for the 
sweetness and mellowness of their tones, which contrast 
greatly with the harsh, clanging sounds to which we 
are accustomed in Europe. They are struck on the 
outside by huge pine beams which are suspended by 
strong ropes. The vessels ordinarily used in worship, 
such as vases, lamps, and incense-burners, are also of 
bronze, many of them being fine specimens of art, 
executed in hizh relief, and finished with much care. The 
demand for art metal work of a high order has thus 
existel for centuries in Japan; and so far as can be 
judged from the specimens of more modern work of this 
description, the hand of the Japanese workman has not 
lost its cunning. In the Japanese Art-Gallery in Grafton 
Street, among many rare and beautiful productions of the 
Land of the Rising Sun, the metal work well deserves 
attention. A pair of darx green-tinted brenze vases, 
fourteen inches high, inlaid with gold, are conspicuous for 
beauty of desiga and workmanship. They are said to 
have occupied the maker seven years, and their curious 
tint is said to be a trade secret. It mu-t be understood 
that it isno mere surface colouring, but is produced by 
the mixture of the metals in certain proportions. The 
work on the rims and necks represent in gold inlay a cloud 
dragon, while the bodies are decorated with four medal- 
lions formed of gold and silver inlays, the shading ob- 
tained by an inlay of gold upon silver being very remark- 
able. The tints of bronzes vary in colour and depth 
from yellow, green, and ruddy to dark brown, and next to 
beauty of design, the tint is a size gud non. A favourite 
design on bronzes is the dragon, a subject which is treated 
with much force and character. 
A plaque of Skakudo—an alloy of gold and copper, 
and black in colour—set in a bronze mounting, repre- 
senting the bamboo, is remarkable- as showing the 
care and labour expended by the Japanese artist in 
working out details. The design represents a meeting 
between the twelve chief disciples of Buddha; the’ in- 
laying of the figures, trees, flowers, &c., is of gold and 
silver, with various tinted compositions, and stands 
out from the dark background of the alloy with much 
brilliancy. One of the compositions employed for shad- 
ing is called shréu-ich?, and consists of three parts of 
copper to one of silver. Both these alloys are favourite 
compositions of the Japanese artist. The minute inter- 
laying of gold and silver in another plaque, about eighteen 
inches in diameter, with a curvilinear border, exhibits 
marvellous skill. The body of the plaque is of iron, and 
the border is adorned with grape-leaf and fruit patterns, 
the former being of gold, the latter of silver. This is the 
work of Komai, of Kioto, whose fainily held the office of 
sword-mounters to the Court. Swords in the olden time 
