PLAGUE, RATS AND FLEAS. 27t 



early in the epidemic of plague in Sydney in 1900 to the unusual 

 prevalence of fleas in the infected quarters. He writes : " At the time 

 the rats were dying in large number upon the whaif , to which attention 

 was called above ; the fleas there were so numerous that the labourers 

 tied string round the bottom of their trousers to protect themselves 

 against the onslaughts of the vermin" ( l2) . Again, in connection with 

 the rat epidemic of plague at Cardiff in February 1901, I quote from 

 the Local Government Board Keport for 1902 : " Fleas in considerable 

 numbers were observed on the white flour sacks in the warehouse 

 mentioned " <' 3) . I have on more than one occasion been told that before 

 an outbreak of plague occurred, fleas were noticed to be very prevalent ; 

 the only wonder is, as Tidswell (l4) has expressed it, that such a fact 

 should have been noticed at all, for the social status and domestic habits 

 of most people among whom plague occurs is not such as to invest 

 a little incident of this sort with remarkable novelty. Finally, there 

 are many facts to my mind which cannot be explained on any other 

 hypothesis ; I will only mention a few of them here. 



Mr. Nigel Paton, who is in charge of a large oil store in Bombay, 

 wrote to me after reading my paper published in the Medical and Phy- 

 sical Society's Transactions last year, ( 15 > that he had been at a loss to 

 explain why every year during the plague epidemic he lost several hands 

 employed by him in the office connected with the store, while, since 

 the plague has broken out in Bombay, he did not remember a single death 

 from plague having occurred among the hands he employed in the store 

 itself, although the hands employed in both departments lived in much 

 the same manner, and in the same infected surroundings. Unfortu- 

 nately he could not support the statement by statistics, but he said 

 it was a well-known fact in the office, and had annually been commented 

 on. His explanation of the fact now is this, that the men in the oil store 

 itself were constantly handling oil, to such an extent indeed, that their 

 bodies were covered with it ; and he presumed that probably the smell 

 of the oil, or some other cause connected with the oil, prevented the 

 infected fleas biting the oil workers, and so they escaped the disease. 

 Now Mr. Paton's experience is by no means unique. In 1797 it was 

 observed by Mr. Baldwin, the British Consul in Egypt, that among the 

 millions of inhabitants who died of plague in that country in the space 

 of four years, not a single oilman or dealer in oil had suffered < l6 >. 

 Sir J. McGregor remembered that all the men employed in applying 



