SCIENTIFIC SUMMARY. 
279 
be made to settle the question as to whether the discovery of photography 
is to date from 1780 or 1791, with an exchange of laurels from the head of 
France to that of Britannia ; or whether the discovery is only “ a mare’s 
nest;” — we incline to the latter opinion. 
The Question as to the Invention of the Triplet Lens. — Mr. Sutton has 
on several occasions since the appearance of the Jury Report on 
the Photographic Department of the late Exhibition, questioned Mr. 
Dallmeyer’s claim as the inventor of the unsymmetrical triplet lens, 
stating that the idea had been taken from hi3 own “ symmetrical ” de- 
scribed some years since ; but lately he has gone a step further, and proves, 
by a photo-lithographic copy of a letter addressed to the late Andrew Ross, 
bearing date November 13th, 1858, that he likewise suggested the proper 
construction of an unsymmetrical triplet, that Mr. Dallmeyer had access 
to this communication, adopted his idea, but has modified his suggestions 
“ for the worst.” Mr. Dallmeyer retorts that he is no way indebted 
to Mr. Sutton, but that they are mutually indebted to Mr. Roth well 
for the idea of a triplet ; and that he (Mr. Dallmeyer) was the first to 
produce a lens of this construction, a lens admitted by practical photogra- 
phers to be a valuable addition to their apparatus — a claim that cannot be 
denied ; while it remains for Mr. Sutton to prove that the triplet lens, as 
arranged by him, is superior to the one already before the public ; for, in 
all these cases, “ the proof of the pudding lies in the eating,” and atrial of 
the two modifications under parallel conditions will be the only way in 
which it can be satisfactorily determined. 
Photography in its application to the Microscope again seems to be 
claiming the attention it deserves after a lull of some ten years. In the 
last number of this Review a description was given of a “ Patent ” micro- 
graphic camera, invented by a Mr. Eden ; but a letter appeared in the 
Chemical News and the British Journal of Photography, from Mr. Highley 
the optician, pointing out the practical shortcomings of this “ patent ” 
arrangement, and describing the construction of the apparatus he employs 
for securing negatives of microscopic objects for his educational photo- 
graphs for the magic-lantern. He points out the necessity of using a 
camera with a free range of adjustment from 12 to 30 inches, instead 
