438 
JOURNAL, R.A.S. (CBYLON). [VOL. XVIII. 
The name of M. Lumiere of Paris and Lyons is also a 
conspicuously familiar one in conjunction with colour photo- 
graphy. More recently the methods utilized by M, Lumiere 
have closely coincided with those of the perfected Ive's carbon 
system, but was formerly more especially connected with a 
processby which three stained collodion films were successive- 
ly superimposed upon one another in accurate optical contact. 
A remaining colour photographic method that especially 
demands notice is that distinguished as the Lipmann 
process. This process as a matter of fact represents the 
only one by which natural colour photographic images have 
been taken directly on an exposed plate. In order to 
accomplish this a bath of mercury is temporarily placed in 
contact with the emulsion surface of the exposed specially 
prepared photographic plate and upon which surface the 
refracted rays of light are registered with a greater or less 
degree of colour accuracy. This, from a scientific stand- 
point, most interesting method of colour photography is as 
yet, however, only in its initial phase of development. 
The failures are multiple and the successes few that 
have been achieved in its practical application. It would 
seem at the same time to possess latent possibilities that 
may lead to very important future developments. 
I will propose now to enter a little more fully into the 
details of that process by which the majority of the examples 
to be brought before you this evening were constructed, and 
which is a development of the Ive's system most generally 
known as the "Sanger Shepherd" process. Any ordinary 
camera adapted to time exposures and to which the requisite 
three-colour screens can be fitted can be utilized for this 
interesting branch of photography ; and as all the parti- 
cular descriptions of screens, plates, and other materials used 
are now made the specialite of a leading London photo- 
graphic manufacturing firm, Messrs. Sanger Shepherd & Co., 
it may be anticipated that colour photography as exemplified 
by this particular trichromatic process will be taken up 
very extensively. 
