_Talc for Collodion Pictures._--Should any of your photographic friends
wish to transmit collodion pictures through the post, I would suggest
that thin plates of talc be used instead of glass for supporting the
film; I find this substance well suited to the purpose. One of the many
advantages of its use (though I fear not to be appreciated by your
archæological and antiquarian section) is, that portraits, &c., taken
upon talc can be cut to any shape with the greatest ease, shall I say
suitable for a locket or brooch?