The morning news. [volume] (Savannah, Ga.) 1887-1900, 1900-01-21

PAPER or magazine illustration. Only the
faintest and most unsatisfactory notions
OF the objects pictured can be present
ed. There is no suggestion of solidity, of
perspective, of rounded form.
In such circumstances scientists wish
ing to publish illustrations showing the
results of microscopic investigation have
sometimes resorted to line drawings from
the plates. But even these have been I'M
satisfactory, because lines indicate alto
gether too much sharpness of outline.
Protective Photography.
Recently, however. a scientific photog-
rapher in New York has succeeded in
making enlarged photographs of micro
scopic objects, in which many of the
faults shown in microscopic photographs
are avoided. A certain degree of sharp
ness has been lost, but rounded and other
irregular surfaces are made to appear as
they really are, and not fiat, as the same
surfaces would appear in photography
taken with microscopic lens. He calls his
work protective photography" The
| principles he Utilities have long been
known and taken advantage of, but he
seems to be the first to use them for
making large pictures of diminutive
things, such as small sections of animal
tissue, minute insects and the like. And
| as it is impossible to patent his plan, it
| is likely that it will he used extensively
/ in the future in preparing illustrations
/ for scientific publications. of various sorts
] works on entomology, and the like.
| Professional photographers and many
| amateurs will understand his method
| when it is explained that protective pho
| Biography" is a modification of the methods
| used in a reducing and charging camera.
| To those not conVersant with photography
| ii may be explained that the same princi-
pie is employed in the magi lantern.
| Magic lantern slides are never more than
! two or three inches in size, yet the image
thrown upon the screen covers many
| square feet. Its size depends upon the
| distance between the light and the slide
and between the lantern lense and the
! screen. The rays of light passing throug h
the lens spread as they extend outward,
/ showing larger on the screen in exact reia-
| ton to the space separating it from the
| lantern. Were the light strong enough,
| and the image on the slide of sufficient
| defniteness, there would virtually be no
| limit to the possible magnifying power of
| the lantern. Were the screen a gigantic
| sensitive plate the result would be an
enormous Photographic negative. All pho
| tographic engagements are made by the
utilization Of this principle.
Magniiics with Low Power Lens.
From this explanation it will be plain TO
| all possessing even slight knowledge of
| photography that pictures showing high
| magnihcation Of minute objects can be
| readily taken with a lense of compare
| tlvely low power. The chief difference be-
tween protective photography" and or
| binary enlargement work is this: In the
latter the enlarged negative or print is
produced by passing the light rays
| through a glass positive or negative ex-
actly as they are passed through the slide
| In a magic lantern and thrown up on
| a sensitive plate or seusitized paper, while
in protective photography the image of
the object to be photographed is itself
thrown up"
| IF the object be transparent as a sec
ton Of the pia mater-the covering of the
! brain-or other transparent tissue, the
| light may be passed through II to show its
structure. If the object be opaque, as an
insect, the light is allowed to fall upon ii
exactly as I'm ordinary photography The
| form OF camera used virtually differs from
| the ordinary camera only in being deeper,
so that the plate may be farther removed
| from the tense.
! A fair idea of the different results OBJ
| tanned by microscopic and protective"
photography may be obtained from the
contrasted representations Of lung tissue
| accompanying this article. The larger
picture is taken from protective photo
| on. nh fha ognaIlaf. from. ,v,gnras,xsr.io