PHOTOGRAPHING BACTERIA. II3 
affairs. He had no objection to its being called an affiliated 
Society of the Field Naturalists’ Society, with which he had strong 
sympathy. Dr. Russell proposed that the consideration of the 
subject be postponed till another meeting, and in the interval the 
opinion of the Scientific Society could be taken as to the question 
of affiliation as proposed. This proposition met with general 
approval, and a provisional committee, consisting of Mr. Ferguson, 
M.P., Mr. W. I. R. Crowder, Dr. Barnes, Mr. Sinclair, Mr. Hep- 
worth, Mr. Hall, and Mr. W. Duckworth was appointed to attend 
the annual meeting of the Scientific Society, on the 3rd of May, 
and report to an adjourned meeting on the following evening. 
Votes of thanks to Mr. Hall and the chairman terminated the 
proceedings. 
PHOTOGRAPHING BACTERIA. 
By Dr. Kocu, 
(Extracted from the Photographic News, Oct. 22nd, 1880.) 
HE following method for producing photographs of the bacteria 
may be of interest to some of our readers, who will see that 
it differs in no respect from that of Dr. Woodward, and published 
many years ago in the Monthly Microscopical Journal :— 
“The photo-micrographs that I forwarded to Professor Lister 
represent, for the most part, images magnified seven hundred 
times. I employed, for the purpose of securing them, an im- 
mersion lens by Siebert and Kraft, opticians of Wetzlar; and I 
may say that the instruments of these makers are particularly well 
adapted to micro-photographic work. Lens No. vii. was the 
instrument chosen by myself, and for my own part I prefer the 
system to that of Hartnaeker ; I prefer it even to the oil immersion 
system of Zeiss, when the latter is not provided with a correction 
lens, or Woodward’s so-called amplifier. 
“The tube of the microscope—-or, rather, the tube in connection 
with the microscope—was capable of drawing out to a length of 
two metres (six feet). The microscope and tube were horizontal, 
and, in place of the eye-piece, a small bellows camera was attached, 
care being taken, of course, to exclude light at the junction of tube 
and camera. I employed the wet collodion process, practising it 
in the ordinary manner. 
“I managed the lighting of the object to be photographed in the 
manner following. The object was a thin microscopic preparation, 
and so that sufficient illumination should be concentrated upon it, 
I employed sunlight, reflected by means of a heliostat. A wide- 
angle condenser was, moreover, employed to concentrate this 
