ili:a r.iA'/i7/;/i'.s of the i'lacie 



'.t; 



plaji'iU' r<';i|)])c;irf(l in all ])arls of that city in i'.M)7 alter liaxin;;' Ix'cn 

 stani])('(l out in (Innatown in 1!)()() was |)r()liai)ly dnc to tlic scattering' of 

 the city'> imIs dnrinu tlic eartli(|nake and fire. I'',ner.uv was directed at 

 oiK'o lio\ve\cr toward the extermination of the I'ats, fully one million wen' 

 killed, and as a result the plauiie was checked. 



It i> known now that an outhreak of |)la<;iie is always preceded hy a 

 similar scoiu\u'(' amoni; rats, hecause huhonic plague is primarily a rat disease. 

 \et so l)liiid has the woi-ld lieen to the interrelations of animals and man 

 in cases of infectious disease that not w it hstanding the terrihU' inroads made 

 by the "hlack death" in xarious parts of the world during liistoric times, 

 no report is made ])rior to ISOO of the coincident inroad upon rats. It was 

 in 1S94 that \'ersin of the I'asteur Institute isolated the biihonie plague 

 bacillus [BiiciUit.< pc.s-tis) and ])ro\('d the germ to be the same in rats and 

 man. Hut this was only a few years ago. Knowledge came late. Bubonic 

 plague had well-nigh encircled the globe before this, breaking out first in 

 seaboard ])laces ])robably ha\ing traxclled from counti'y to country among 

 ship rats. The efi'ect of this discoxcry which tiu-ned the att.ick upon the 

 rat is shown well in Bombay where the death rate of 20,788 in 1903 was 

 reduced to .■),107 in ]<)()0. 



As yet the rats of the northeastern United States are not plague in- 

 fected, but this is not necessarily a permanent condition. There may be at 

 any time in Xew York or other eastern seaport an outbreak of i)lague such 

 as occurred in Sutt'olk, England, last S(>])teml)er. For plague is not limited 

 to the tropics or semi-tropics although it has flom-ished there because of 

 less sanitary conditions. l-Meas are common in the eastern states. In- 



(iuiri(>s concerning them reach the Mu- 

 ;^ seum at all seasons of the year, but 



Mashing lii.s (ace and scratcliiiiK his ear 

 in rat conu-niment. The brown or ' 'Nor- 

 way" rat, Mris (lecumnnus, whicli lias to- 

 day colonized well nigh the whole earth driving to the wall the black rat, Mnn raUus, the 

 species of romance and history. He is more "sinned against than sinning" in the plague 

 matter for bubonic plague is a rat disoa.se, in any given outbreak the rat mortality being to 

 hiunan mortality as ten to one 



