David Bloom

A SIMPLIFIED METHOD OF PREPARING PENCILS OF CARBON DIOXIDE SNOW

Carbon dioxide snow, which was introduced by Pusey 1 in 1907, has proved a valuable remedy, particularly in the treatment of angiomas, pigmented nevi and lupus erythematosus. Many dermatologists for convenience have discarded the liquid carbonic acid tanks formerly used, employing commercially prepared carbon dioxide snow, from which, by means of a hammer and chisel, pencils of the desired size and shape are prepared. Recently I found that pencils can be prepared rapidly and conveniently from carbon dioxide snow with a copper tube. I use for this purpose one of the tubes from the cold cautery set of Lortat and Jacob. When the hollow of the warmed tube is pressed against the carbon dioxide snow, a pencil can be made in a few minutes. If the tube becomes cold, it may be removed from the snow and warmed. The size and shape of the tube determine the size and shape