126 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
replaced in fig. 25 by a sponge J ; E is a porcelain vessel. The liquid 
is slowly drawn off in the direction of the arrows, leaving the suspended 
matter cm the slide or cover-glass. The rate of filtration, which can be 
regulated by the pressure of the spring, and in some cases by pressure 
of air from an inflated rubber bag, must be so slow that no suspended 
matter is carried into the filter. For the larger organisms in water 
20 ccm. should take three hours ; for bacteria, 1 com. should take twenty- 
four hours, and for urine analysis, 2 to 20 ccm. should take from one to 
two hours. 
(4) Photomicrography. 
Some New Points in Photomicrography.* — Mr. W. H. Walmsley 
calls attention to a new form of camera which he has recently introduced 
under the name of the ‘‘Autograph.” It was devised in order to remedy 
some defects in the instrument known as the cc enlarging, reducing, and 
copying pliotomicrographic camera,” which the author placed on the 
market early in 1882. 
The base, or platform, of polished wood, 26 in. long, stands 
upon three very short feet, the front end being heavily weighted. At 
the other end of the platform is bolted a stout iron frame, 24 in. 
long, which carries the camera. The latter slides freely in parallel 
grooves, and can be fixed in any position by a binding screw which 
passes through a slot. By means of a joint at its base, the frame carry- 
ing the camera can be inclined and firmly held at any angle. 
The camera-box is furnished with leather bellows extending to 
twelve inches, and is fitted with a reversible back, carrying both focus- 
ing screen and plate-holder. The ground glass of the focusing screen 
can be replaced by plate-glass when very fine adjustment is to be made. 
The plate-holder is double, and fitted with inside kits to carry 3J by 
4£, 2J by 2^, or lantern plates, as well as the full size plate, 4 by 5. 
For focusing when the Microscope is in the horizontal position, a 
short rod is attached to the base board on the right hand of the camera. 
It carries at one end a large milled head, and at the other a pulley - 
wheel with Y-shaped groove in its periphery, a corresponding groove 
being also turned in the micrometer screw of the Microscope. This 
pulley wheel slides along the rod so that it can be placed in a line with 
the fine-adjustment screw, where it is firmly held by a screw. A fine 
cord passing round the two grooves effects the movement of the micro- 
meter screw when the milled head is turned. 
The platform is long enough to carry Microscope, lamp, and bull’s- 
eye condensing lens. 
As regards artificial illumination, the author considers that the new 
acetylene gas lamp is the ideal light for photomicrography. 
Advances in Photomicrography. I — Herr G. Marktanner-Turner- 
etscher gives an account of the advances which have been recently made 
in pliotomicrographical work. He draws attention to new and improved 
apparatus, and gives brief abstracts of the various papers on the subject 
recently published, most of which have been already noticed in this 
J ournal. 
* Amer. Micr. Journ., xvi. (1895) pp. 3G9-78. 
t Eder’s Jahrb. f. Pliotog. u. Reproductionstochnik, 1894 and 1895. 
