174 
Transactions of the Society . 
IV. — A new Form of Photomicrograjohic Camera and 
Condensing System. 
By E. B. Stringer, B.A. 
{Bead loth December, 1897.) 
The apparatus which Mr. Watson Baker has kindly undertaken to 
submit to the Society on my behalf, is an attempt to facilitate the 
work of photomicrography, especially with high powers, and to afford 
an illuminating system more perfectly corrected, more powerful, and 
more under control, than has hitherto been available. 
The baseboard is confined to that part of the apparatus which 
carries the illuminating system and Microscope, the further end of 
the camera being supported by a massive wooden block. To this are 
attached two long brass tubes, on which slide the supports for the 
bellows, and which themselves slide in slightly larger tubes attached 
to each side of the baseboard. By drawing out these inner tubes with 
the block, and sliding the bellows supports the other way, the camera 
can be extended to 40 inches, or it may be closed up to 11 inches ; 
but at whatever length it may be used, there is no baseboard pro- 
jecting beyond the end of it, and the focusing screen is always in 
the most convenient and accessible position, namely at the end of the 
bench, where the worker can be comfortably seated. Also the firm 
support of the massive wooden block is always immediately beneath 
it, conferring the greatest possible solidity and freedom from vibra- 
tion. 
A door is provided at the side of the camera for the examination 
and adjustment of the image in situ , when a white card is substituted 
for the ground glass or other screen. 
If it should be necessary, though in practice it very seldom is, to 
look down the Microscope when it is in position, the camera can 
readily be drawn backwards altogether out of the way of the observer’s 
head. And it will be seen that the whole camera can in a moment 
be entirely removed, and the Microscope used, if so desired, for screen 
projection. 
I have found that the secret of avoiding vibration is to clamp 
down nothing, but to let everything rest by its own weight on as 
large a surface as possible. To increase this effect, and to bring the 
apparatus into firm and intimate contact with the bench (and also to 
help to absorb vibration), it has underneath it a layer of sheet cork 
one-eighth of an inch thick, below which is another layer of felt also 
one-eighth of an inch thick ; on these it rests with great firmness, 
and at the same time slides easily enough when pushed. 
