its metallic or pure state and most of the compounds are impure. Radium
banks have been established in London, Paris and New York.

Whenever radium is employed in surgery for an operation about fifty
milligrams are required at least and the banks let out the amount for
about $200 a day. If purchased the price for this amount would be
$4,000.




CHAPTER IV

MOVING PICTURES

Photographing Motion--Edison's Kinetoscope--Lumiere's
Cinematographe--Before the Camera--The Mission of the Moving
Picture.


Few can realize the extent of the field covered by moving pictures.
In the dual capacity of entertainment and instruction there is not a
rival in sight. As an instructor, science is daily widening the sphere
of the motion picture for the purpose of illustration. Films are rapidly
superseding text books in many branches. Every department capable of
photographic demonstration is being covered by moving pictures.
Negatives are now being made of the most intricate surgical operations
and these are teaching the students better than the witnessing of the
real operations, for at the critical moment of the operation the picture
machine can be stopped to let the student view over again the way it