SAFE X-RAYS.

Bay of Plenty Times, Volume XXXVIII, Issue 5498, 20 April 1910, Page 4

SAFE X-RAYS.

The fin 4 onqn. ring of X- uys and 'he successful ban nssing of them fur the treatment of dispa>ed coiditrmp without danger to the operator have been on u.;ut a c!e< ided step nearer \>y ■a clever arrangemfnt of a[ para' us juit instalkd at the London Hospital It will be remembered, says-th Doily Wail, that Dr. Hal'-^rfwaids and Mr Harry Cox snffere-1 serious injuties through experiments with X-rays. The initial principle of the apparatus, which was explained to a medical correspondent by Dr. Blaekall, the chief operator, is that the operator cannot in advertently come within the range of the rays. A middh-agsd woman with a red and angry lupus scar on her face who came for treatment afforded a striking object lesson of the advances in treatment by X-m s which have been made in the past few years. The patient lay on a leather cauch in a white-painted cubicle, iv the front wall of which were two ordinary glast windows and a door having two glas* ptnels An X ray tulie surrounded by a shield of Bohemian lead glass ( imp r meable to the rays) was arranged to protect her from the light at every point except the one where a narrow shaft of rays could fall directly on the lupus patch. The patient being in position, die operator left the cubicle, carefully closing the door behind him Then and then only, thecurrent was turned on The ordinary- looking partition with its commonplace looking gl-ss windows •nd door panels held the key of the At uatLn i'he glass — more than a quar ter of an inch thick— was a Bohemian lead glass, and though perfectly trans parent was impervious to the rays, while the wood work of both diorand partit ton was a sandwich of two layers of •half inch boards euclosing two sheets of lead and iron, each an eighth of an inch thick " In testing that glass, " said an in formant, "it was bombaidel by rays from an X-ray tube held close to it while a photographic plate was placed on it 3 other side. After an hour's ex posnre the plate was still unaffected. ' ' Even the spark gap (which warns the operator of any rise in tbe vacuum oi an active tube) and the mechanism for lowering the vacuum are controlled bj the operator from his position of safety ontside the light-chamber.. A further safeguard is an automatic switch on the door leading into the light chamber. If the operator nnthinkly attempts to enter while the light is^ on the mere opening of the door breaks the electric circuit and the yel'ow greeu flickering immediately ceases in the tube.