The sodium chloride alibi.

From the Photographic News we take the following: The use of paper coated with a gelatino-citro-chloride emulsion in place of albumenized paper appears to be becoming daily more common.

We wish first of all to refer to an elaborate series of experiments by Lionel Clark on the effects of various toning baths used with the gelatino-citro-chloride paper.

All the sulphide ores in Bolivia contain sufficient copper to form the quantity of cuprous chloride requisite for the first stages of roasting, in order to render the silver contained in the ore thoroughly amenable to subsequent amalgamation.

By some practitioners the operation is performed with the animal standing, local anæsthesia having been first obtained by the use of cocaine, or an ethyl chloride spray.