Part 2 — APPENDIX IV. ANALYSES OF JAPANESE MIRRORS.

MM. CHAMPION AND PELLET (Industries de l’empire Chinois, p. 64) give the following composition for Chinese mirrors:

Copper50·8

Tin16·5

Zinc30·5

Lead2·2

———

100·0

———

Dr. Geerts gives (Trans. Asiatic Soc. of Japan, vol. iv., p. 40), for the alloy used in one of the largest mirror-foundries in Kioto:

Copper80

Tin15

Lead5

——

100

——

And for mirrors of inferior quality:

Copper80

Lead10

Shirome10

——

100

——

Shirome is a natural sulphide of lead and antimony from Choshiu or Iyo.

Professors Ayrton and Perry (Proc. Roy. Soc., 1878) give:

For mirrors of first quality:

Copper75·2

Tin22·6

Iyo Shirome2·2

———

100·0

———

For mirrors of second quality:

Copper81·3

Tin16·3

Iyo Shirome2·4

———

100·0

———

For mirrors of third quality:

Copper87·0

Tin8·7

Iyo Shirome4·3

———

100·0

———

For mirrors of fourth quality:

Copper81·3

Tori Shirome16·3

Iyo Shirome2·4

———

100·0

———

For mirrors of fifth quality:

Copper71·5

Tori Shirome28·5

———

100·0

———

The mercurial amalgam used in polishing the mirrors consists, according to Dr. Geerts (op. cit.), of quicksilver, tin, and a little lead. Ayrton gives it as one of tin to one of quicksilver. Champion and Pellet (op. cit.) give the composition as:

Tin69·36

Mercury30·0

Lead0·64

———

100·00

———

On the occasion of the delivery of this discourse the Author exhibited a collection of thirty-four Japanese mirrors, and by the aid of a lime-light lantern displayed their magic properties upon a translucent screen. He also exhibited sundry experiments with Laurent’s apparatus, and showed the effect of heating mirrors.