Page:Popular Science Monthly Volume 58.djvu/258

250 were given regarding the preparation of sinks and their care, with a direct indication of the danger of transfer of typhoid fever by flies. These instructions were not followed, and the result was that over 21 per cent, of the troops in the national encampments in this country during the summer of 1898 had typhoid fever, and over 80 per cent, of the total number of deaths during that year were from this one cause.

This condition of affairs was not confined to the United States. An epidemic occurred in the camp of the Eighth Cavalry at Puerto Principe, Cuba, in which two hundred and fifty cases of the fever occurred. The disease was imported by the regiment into its Cuban camp, and Dr. Walter Reed, U. S. A., upon investigation, reported to the Surgeon-General that the epidemic "was clearly not due to water infection, but was transferred from the infected stools of the patients to the food by means of flies, the conditions being especially favorable for this manner of dissemination. . . . "

In all the published accounts, and in all literature of closely allied subjects, the expression used in connection with the insects has been

simply the word 'flies.' Nothing could be more unsatisfactory to the entomologist than such a general word as this, except it were taken for granted that the house-fly (Musca domestica) was always meant. It has not apparently been realized that there are many species of flies which are attracted to intestinal discharges, nor does it seem to have been realized that, while certain of these species may visit, and do visit, food supplies in dining rooms, kitchens and elsewhere, many others are not likely to be attracted.

In 1895, the writer made a study of the house-fly, not from this