138 Joty—On a Method of Photography in Natural Colonies. 
NOTE ADDED IN THE PRESS. 
I have recently ascertained that Ducos du Hauron 30 years ago, at the con- 
clusion of a lengthy French patent for colour reproduction by triple projection, 
suggested the use of a screen lined in colours for combining the three images 
in one. The fact that his theoretical colour principles were erroneous and 
that consequently no practical result is possible on the procedure he suggests, 
probably accounts for the absence of any record of anything actually accomplished 
in this direction.—(June 3, 1896.) 
