Letter of the Day: June 25

Curatorial Records: Numbered Correspondence 744

This report was recalled and a later one made. (See Record Card No. 744)

Subject: Auto-Sterilizing Clinical Thermometer Cases.

War Department,
Surgeon General’s Office,
U.S. Army Medical Museum and Library,
Corner 7th and B Streets, S.W.,
Washington, D.C., June 25, 1895,


To the Surgeon General, U.S. Army.
Washington, D.C.

Sir:

In compliance with instructions from your office dated June 21, 1895, I beg to report that a test has been made, in accordance with your directions, of the Auto-Sterilizing Clinical Thermometer Cases manufactured by Messrs Alfred A. Smith & Co., of this city.

Two tests were made: in the first, the bulb of one thermometer was dipped into a recent bouillon culture of the diphtheria bacillus, and, having been placed in the thermometer case with the disinfecting material, and allowed to remain for one hour, it was then carefully removed with sterilized forceps and placed in a tube of sterilized bouillon. The bulb of the second instrument was thoroughly smeared with a recent culture of Streptococcus pyogenes on agar, and was treated in the same manner as given above for the other instrument. This experiment was made about 3 o’clock on June 22nd. At the present writing, after a period of sixty-seven hours, no growth has appeared in either tube.

A second experiment was performed as follows: The bulb of one thermometer, carefully cleansed, was thoroughly smeared with a recent culture of the diphtheria bacillus on blood serum, while that of the other instrument was smeared with a recent culture of Streptococcus pyogenes on agar. After thirty minutes exposure in the cases, the instruments were removed with sterilized forceps and placed in tubes of sterilized bouillon. Twenty-four hours later no growth is to be observed in either tube.

While it is believed that this thermometer case admirably answers the purpose for which it was intended, it is desired that a more complete test of the case, using shorter intervals of exposure, may be carried out. When this has been accomplished an additional report will be submitted.

Upon examination it is found that the auto-sterilizing fluid is nothing more than a solution of formaldehyde.

Very respectfully,
Walter Reed,
Surgeon, U.S. Army,
Curator.