v PLAGUE IN THE EAT 91 



perhaps two or three others, in respect of which it is not clear what 

 measures were taken. 



As regards the nine vessels in which rat plague alone was ob- 

 served, the disease is alleged to have spread to places on shore in one 

 instance, viz. the Y., account of which has been given on a previous 

 page. So far as these places — Port Louis, Reunion, and Tamatave — 

 are concerned, it seems probable that plague appeared at Port Louis 

 within a month of the Y. having called there. Tamatave seems to 

 have been plague-infected about the time of that vessel's arrival — 

 Reunion not for several months later. The Y., it will be remembered, 

 never had any suspicious human sickness on board during her long 

 voyage of some three months ; and it may be doubted whether the 

 rat disease really was plague. One of the crew attributed the rat 

 mortality on the Y. to poison which he had laid down for them. In 

 the remaining eight vessels no spread took place from ship to shore \ 

 and this notwithstanding that, in at least five of these vessels, the 

 cargo had been partly or wholly discharged before the infected rats 

 were discovered, and therefore before any measures had been taken 

 to secure destruction of rats. Indeed, in the case of the Chios, at 

 Hamburg, part of the cargo had been conveyed into the interior. In 

 none of these eight vessels, however, did plague attack the persons 

 unloading or handling the cargo, nor is plague known to have made 

 its appearance among persons or rats ashore. 



Our own experience at home is not without bearing on this 

 question as to what degree of risk there may be of conveyance of 

 plague infection from ship to shore by means of rats. In the earlier 

 days of the present recurrence of plague in epidemic form, no 

 measures whatever were taken as regards rats in our home ports ; 

 and, indeed, even to-day such measures are, in most of our ports, 

 limited to ships known to have plague on board. Yet, notwith- 

 standing our enormous mercantile traffic with all parts of the world, 

 extension of plague on shore has taken place in four instances only, 

 viz. twice at Glasgow, once at Liverpool, and once at Cardiff. It is 

 further to be noted that in the first outbreak of plague in Glasgow (in 

 1900), notwithstanding careful bacteriological examination of large 

 numbers of rats, no single instance of rat infection was discovered j 

 while in the Liverpool outbreak in 1901 there was like absence of 

 rat infection. In Cardiff, however, plague made its appearance, in 

 1901, among rats on shore, but it was accompanied by only one 

 human case. These facts, like others already cited, tend to suggest 



