77 2 
Notes. 
[November 
compared with that of 1877, was 1,955,876 tons. The produc- 
tion of pig-iron in Germany during 1878 was 2,124,444 metr. 
tons; zinc, 94,954; lead, 84,372; copper, 9541 ; tin, 831 ; anti- 
mony, 1245; coa b 39,429,308 ; lignite, 10,971,117; asphalte, 
47,329. The total amount of pig-iron produced in France in 1878 
was, according to “ Engineering,” 1,508,246 tons, most of which 
came from the Meurthe-et-Moselle. Pig produced with the aid 
of coke is greatly in demand, and is driving out charcoal pig and 
mixed sorts. 
An attempt is contemplated to work coal-mines in the neigh- 
bourhood of Ching-men-Chow, not far from Tchang. Boring 
operations were commenced late last autumn. The coal-pro- 
ducing country appears to cover an extent of 758 square English 
miles, 15 long by 5 broad. There are two layers of coal, one 
above the other. It is supposed that 1,200,000 tons of coal can 
be raised from Wotzukow, and 800,000 from San-li-kang, at the 
rate of 40,000 tons a year. The supply thus would last at least 
forty years. It is highly probable that further explorations will 
bring to light fresh beds, as these discoveries are the result of 
merely the first investigations. Specimens of all the native and 
foreign coal procurable in China have been analysed together, 
and the new coal has shown itself superior to all for smelting 
purposes. 
Requiring large quantities of platinum for his eledtro-chemical 
telephone, Mr. Edison issued, some few weeks ago, a circular 
letter of enquiry with regard to the possible occurrence of pla- 
tinum in various parts of the United States. From the 
“ Scientific American ” we learn that Mr. Edison received some 
three thousand replies to his letter. Platinum, instead of being 
an extremely rare metal, seems to be widely distributed, and to 
occur in considerable abundance. It is found where gold occurs, 
and Mr. Edison thinks he can get 3000 lbs. a year from Chinese 
miners in one locality. One gravel-heap is mentioned from 
which a million ounces of platinum are expedted ! 
Physics. 
Since the Lontin eledtric light was first used at the Gaiety 
Theatre several important improvements have been effedted. 
The improved machine possesses three advantages, viz. — the 
low speed at which it works, thus reducing wear and tear, risk 
of accidents, and overheating ; the ready division of the light ; 
and the produdtion of alternate currents. The number of dif- 
ferent circuits which one machine can generate, and the number 
of separate lights obtainable from each circuit, are, it is said, 
only limited by the size of the machinery. The machines now 
in operation at the Aldersgate Street Station of the Metropolitan 
