136 Joty—On a Method of Photography in Natural Colours. 
indoors, near a window; stop F/22; a long-focus (113 inches) lens being 
used. A pale-coloured picric acid stained gelatine screen served in all cases to 
cut off the ultra violet and modify the action of the visible violet. 
On the truth of this reproduction I have only to observe that when original 
and photograph have been exhibited together even trained observers could point 
to no error. It is to be remarked, however, that in all cases this degree of truth is 
not attained upon first trial. The correct exposure has to be found, but, once 
found, work upon objects of like nature subjected to like conditions of light, &c., 
is easy and rapid, and the results certain. 
The adjoining picture was direct from nature. The reproduction lacks the 
full richness of the browns, and above all the velvety texture of the petals which 
was very striking in the original especially upon the lower blossoms. It will be 
noticed that the grain is less conspicuous upon this than upon the other pictures. 
This is because the photograph was taken through a screen ruled in two tints 
only, the red-taking and the green-taking. In short, it represents the bunch 
of wall-flowers as they would be seen by violet blind sight. The reds, browns, 
and yellow appear unaffected ; the greens, however, are, as will be noticed, some- 
what harsh. 
The group of bandsmen was taken during Trinity College athletic sports, June, 
1895. Exposure four seconds, F/10, sunny, 4 o’clock in the afternoon. The lens 
was a Goertz anastigmatic. 
The green glass bowl represents an Uranium glass possessing fine dichroic 
effects in yellow and green. These effects hardly reappear in the reproduction, 
but the effect of transparency is correct. This picture was one of the earliest 
taken. 
Other subjects have also been dealt with. The solar spectrum taken according 
to Maxwell’s curves is seen to extend on the photograph from the C red to the H 
lines. The blue-green is not quite correct. Many of the Fraunhofer lines are re- 
produced. The reproduction of bright metallic objects has been tested by photo- 
graphing a highly lacquered microscope in brass and German silver. Various 
interiors, as the hall of the Engineering School, Trinity College, have been taken. 
Among out-of-door subjects, a view in the quadrangles of Trinity College shows 
the new red-brick buildings; the red hawthorns in blossom, and figures in the 
foreground in grey and black suits, with University Rowing-Club blue on straw hats. 
Other views of the College Park; fields and chalets in Switzerland (F/18, 3 sees. 
September, 10 o’clock, clear sunshine). A portrait from life, of Mr. Henry H. 
Dixon, of Trinity College, shows that the most faithful reproduction of flesh tints 
is possible. A bunch of pansies in a Japanese bowl, reproducing the velvet of nature 
upon the darker hues of blue-black and tawny-brown, suggests how the association 
