154 THE RISE AND PROGRESS OF PHOTOGRAPHY, 
upon us so also came the means of preventing — and if the 
The former may yet be a 7 way off, but the sb of 
Béquerel, a de St. Victor, Vidal, Woodbury and ot have 
rap eeded that for commercial purposes there e already 
three arent in use. e turn to the labten requirement and 
- find that success has bountifully rewarded the many patient 
months and years of trial in this direction, for photography which 
has alre we: in ma ny cases Pi a ied the a of the artist or 
idity of printing, printin 
independently of hie Tight es ate in es tone an 
value of the proofs, printing in any colour desired, cheapness, with 
the correctness and perfection of outline, detail, &e., generally 
ae in photographs. No remarks need follow these pana 
to show the immense utility of such processes, but a s extract 
ed an article in the London Times on the value of ae repro- 
po ac yar of — pictures of the great masters would not be 
mal a 
“Tf pict lp art, is, indeed an educational influence of a high 
order, and if it is desirable to yet pemaly of form before t 
bar of the young,, the autotypes (mechanical prints) of the great 
s should not only find the places of honor of which ne 
are well worthy, but aie should be in every nursery and schoo 
room in the kingdom 
This is only one ay lication for them; there are astronomy; 
botany, geology, ethnology, ja urisprudence, and a hundred oth 
simply ‘the ceaceti of pictures ae: the means of. light and 
chemical action upon gelatine tine and permanent veers i as 
are used by artists in oil, water colour, or crayon dra 
