PROGRESS IN RADIOGRAPHY.'' 



By L. Gastine. 



The X rays were discovered during the closing months of the year 

 1895, so that but a brief time has been available for the study of 

 their use, though these few years have been fruitful ones. 



We must recognize at the start that the subject has been greatly 

 favored by its element of the marvelous, which appeals so keenly to 

 the public at large. Scientific men know well that prior work of 

 numerous physicists had already prepared the way for Roentgen's 

 half-accidental discovery, but these advances had been cheerfully 

 ignored by the masses, and even by most physicians and surgeons 

 throughout the world. 



Very naturally, then, when it became j^ositively known that with 

 the X rays the skeleton of the hand could be photographed there 

 was excitement everywhere, for it will be recalled that the bones of 

 the hand were the first invisible solid bodies reproduced by Roentgen. 

 The image thus obtained demonstrated an important fact, the per- 

 meability of opaque bodies by the new rays, and on account of the 

 uncertainty as to their character they were christened " X rays." 



With this new process objects were photographed incased in wood 

 (as a compass in its box), money in a purse, the wheels of a watch 

 through its case, and what not; and these amazing experiments 

 served incidentally to demonstrate that the permeability of solid 

 bodies varies with the character of the substance. It Avas learned, 

 for instance, that wood, plaster, cloth, paj^er, are easily traversed by 

 these rays, Avhile metals are less penetrable, especially glass and lead. 



A\liile investigators were establishing empirically by rather trifling 

 experiments the comparative permeability, of difieyent "substances, 

 the medical world was amusing itself making attempts to radiograph 

 various parts of the human skeleton. In every civilized country 

 experiments showed the power of the rays to penetrate the hands, 

 tlie feet, the arms, the legs ; and decided it was hardly possible to go 

 further ; the head forming a recalcitrant mass, the torso and abdomen 



«An abridged translation, by permission, from articles in La Pliototrraphic 

 Frangaise, Paris, 1905. 



151 



