none gave any indication of even temporary illness. Inoculations of pure cultures of staphylococci, as well as of Bacillus verosis (which was at first suspected of being Bacillus diphtheria;) also gave negative results.
From the observations that I have made, it would seem that the bacteria present on paper money are non-virulent and the forms most common are the air forms. Could the loss of virulence be due to drying, the bills having a peculiar dry feeling, no matter how moist the air; or is there some antiseptic action in the ink used for the printing of the bills? I have not taken up the question as to why the bacteria found on money are without virulence, but have confined this study to a careful search for pathogenic forms that might be present on the bills.
The literature on this subject is exceedingly scanty. I have been unable to find any report upon any good scientific work done along this line. Inquiry at the Congressional Library at Washington revealed only four articles—one in Spanish, one in German and two in English, while inquiry among a number of scientific men failed to give me any further assistance with the literature upon the subject of the transmission of infectious diseases through paper money.
That the interest in dirty money, or desire for clean money, is not of recent origin is shown in an article by Dr. Otto Müller,[1] which appeared in 1879. He suggests that money is one means of transmitting the infectious diseases, and although it is extremely difficult to prove an actual case, it certainly offers possibilities. He lays particular emphasis upon the pernicious habit of giving coins to children to play with, especially when they are sick; and also the habit of keeping money under bed pillows, or in commodes or closets where linen or food is kept.
Drs. Acosta and Rossi[2] reported in a Havana journal the results of bacteriological examinations of bank notes made by them. They examined two bills that had been in circulation for some time and found them loaded with germs of various kinds and degrees of malignancy. Cultures were made from the scrapings of the notes and these were injected into the peritoneal cavity of rats and guinea-pigs, most of which died within twenty-four hours, the post-mortem examinations showing signs of peritonitis and congestion of the liver and kidneys. They did not identify any of those germs having "various degrees of malignancy." The fact that the animals died within twenty-four hours indicates that death was not due to the action of any one or more pathogenic forms that might have been present, but rather to the great numbers of bacteria suddenly thrown into the peritoneal cavity.
