A GARDEN OF GERMS 



299 



at once any desired type. A third set 

 of cards is arranged by institutions and 

 shows whicli of our types was received 

 from each lalioratory and which lias been 

 sent out to each, and on what date. 



When a single niicrohe is planted in a 

 suitable jelly medium it will grow and 

 divide again and again (under favorable 

 conditions once in twenty minutes), till 

 in a few days or weeks there will be a 

 colony, perhaps half an inch across, a 

 city of millions of descendants of the 

 original genu, and of characteristic form, 

 texture, and color. The nuiseum of 

 living bacteria has made it possible to 

 prepare an unusually interesting set of 

 such bacterial colonies of different types, 

 which is exhibited in a window case in 

 the hall of public health on the third 

 floor of the Museum. In connection 

 with the albums of wall charts and large 

 photographs on public health circulated 

 by the public education department of 

 the Museum in the schools of the city, 

 special sets of bacterial cultures have 

 been prepared, illustrating the growth 

 and development of bacteria and their 

 effect upon the various media in which 

 they multiply. Six of these sets of 

 twenty cultures were in circulation dur- 

 ing the past year and were used by 

 about one thousand children. Sterile 

 culture plates and media are also fur- 

 nished to the teachers in the high 

 schools so that they may themselves 

 demonstrate the growth of bacteria on 

 plates inoculated with water or milk, or 

 infected by exposure to the air or by the 

 touch of a finger. 



The main object of the bacterial col- 

 lection is however to furnish standard 

 types for the use of teachers and investi- 

 gators in other bacteriological labora- 

 tories throughout the country. It has 

 been the policy of the Museum to dis- 

 tril)ute subcultures from our strains as 

 widely as possible to all responsible 



persons and in all cases without charge. 

 Disease germs are, of course, carefully 

 guarded, being sent only to laboratories 

 of known standing so that thev mav not 

 get into the hands of unauthorized per- 

 sons, while special "teaching sets" of 

 typical non-pathogenic forms are sent 

 to the smaller colleges and normal schools 

 for use in class work. 



Slatifftics of the Museum of Living Bacteria 



Number of Institutions sup- Cultures sent 

 types in plied during out during 



Year collection year year 



The growth of the bacterial collection 

 to a total of six hundred and ninety-five 

 different types, and the development of 

 its distril)ution to such an extent that 

 in 1915 nearly thirty-five hundred cul- 

 tures were sent out to over four hundred 

 different institutions, is indicated in the 

 table above, and the geographical range 

 of the service is strikingly illustrated in 

 the map reproduced herewith. Every 

 university and health department of 

 importance in the field of bacteriological 

 teaching or research in the United States 

 or Canada depends upon our service at 

 the present time; and cultures have been 

 sent to Cuba, to Austria, to England, 

 and to South Africa. 



Many of the cultures which go out are 

 used for teaching purposes as is shown 

 by the great increase of demands in 

 September and January. It is difficult 

 to overestimate the value of such a ser- 

 vice ^ as this to colleges and medical 



' The general appreciation of this service may, per- 

 haps, be suggested by the following quotations from 

 the many letters, which have been received in regard to 

 it, from representative bacteriologists. Doctor Dorset, 

 of the United States Bureau of Animal Industry, writes, 

 '"Your Museum is certainly rendering valuable assist- 

 ance to laboratories by furnishing authentic cultures 



