Evening star. [volume] (Washington, D.C.) 1854-1972, 1912-03-30
NOVEL EXHIBIT GIVEN
Many New Scientific lnstru-
ments on View.
LARGE FIELD IS COVERED
Atomic Arrangement of Molecule
Clearly Shown.
ALL KINDS OF MICROSCOPES
Growing Plants Balanced on Scales
to Show Amount of
Water Absorbed.


ment world was shown at the exhibit Of
the Washington Academy of Sciences at
the New National Museum yesterday.
The Washington Academy has ten or
dozen affiliated societies that cover all
fields of scientific work. from anthropol
| ogy to map making. Some idea of the
range of apparatus shown may be had
| from the fact that there We're represented
| in the show the bureau of standards. the
patent office, the forest service. the bu
reau of animal industry. the bureau of
plant industry and the bureau of ento-
| mology Of the Department of Agriculture.
the geological survey, the reclamation
service. the coast and geodetic survey.
the bureau of mines. the Carnegie Insti-
tuition. the weather bureau and a number
of other divisions of the government
service.
Some of the exhibits were curious and
applied particularly to students. There
was one exhibit from the patent office
showing the atomic Arrangement of a
molecule in the demonstration of chem
istry. There were different shaped and
colored disks and geometrical figures rep
resenting the different elements. These
could be joined together by little hinges
and sleeves. SO that instead Of merely
writing out a clinical formula like H.
5 o.. two atoms of hydrogen, one of sui
phur and four of oxygen could be built
up to show how molecule of sulphuric
acid was constructed. More than that,
the atoms could be grouped in their
proper relation to each other and some
complicated substances containing the
same elements but forming apparently
different compounds could be built up to
show how substances made of the same
atoms might be different in appearance
and specific gravity.
Panorama Camera Shown.
There was an instrument from the
geological survey that was almost I'M
canny in the results it produced. 1t was
nothing but an ordinary panorama cam
era, arranged so that maps could be
made with it. All man had to do was
to go into a region to be mapped and
take three pictures from three different
points of view. In the Office one of these
prints was fixed in a given position on a
drawing board, and. with circle and
swinging ruler, lines were drawn on the
paper from the peaks and other salient
points In the picture. Then the second
print was substituted for the first and
lines ruled from the same features of the
landscape. Where these lines intersected
the feature points Of the map were To-
Gated, just as though a surveyor had
spent weeks in making a detailed survey.
By another ruler and a set Of tables the
height OF the peaks and the depth of the
valleys could be drawn on the sheet. A
man with a camera of this sort could do
enough field work in Is minutes to keep
an office draughtsman busy three or four
days. and at that. the map would be
made faster than II Transcribed from a
field note book.
Many Kinds of Microscopes.
There were all sorts Of microscopes
and accessories. principally from the De-
partment Of Agriculture, showing not
only how microscope slides could be stud
led direct, but how drawings could be
made direct from the microscope.
There was another microscope from the
bureau of entomology mounted over a
troupe Of tree beetles and other insect
pests, illuminated by electric lights, SO
that the visitor could have inspected their
performance except for the fact that
heartless scientist had pinned them all
down so they could not perform. They
were dead, SO that chances were they
would not have performed. anyhow. AS
reason for this work there were sec
lions Of trees shown that had been killed
by the bark beetles that are doing mil
lions Of dollars worth Of damage an
nually.
ment of Agriculture had lot Of growing
plants balanced on delicate scales TO
weigh the exact amount of water that
they absorbed from, or exhaled to. the
1QeTc we're also specimens OF QlS-
eased fruits, with methods Of identifying
the plant diseases.
The agricultural explorers were repre-
scented by grains and useful plants that
had been collected abroad, and are now
being grown as staple crops in this cOun-
try.
Forest Service Apparatus.
The forest service had all the apparatus
and pharaphernalia Of the timber cruiser
and for locating trees and measuring and
marking logs. There was even a simple
little instrument that could be set up on
the ground and the height of a tree
measured by triangulation and read
directly off scale.
plicated instruments were those Of the
| lance and accurate surveying. The
weather bureau had all sorts Of self-re-
cording instruments for measuring wind
the Carnegie Institution had pictures and
markable non-magnetic yacht. the Car
negie, that Is now making q magnetic
survey of all the oceans.
| There were scores of other instruments
covering many fields of scientific activity,
but that would be hard to describe in de-
tail. The Academy Of Sciences is inter
ested in showing its members these late
developments in scientific instruments.
| The opening Of such an exhibition to the
public was an experiment to see how far
| poplI1ar interest extends and IL the ex-