OBSERVATIONS ON THE LUNG PLAGUE OF CATTLE. 703 
so that once introduced the infection became permanent, and 
each city became an independent pestilential centre, from which 
the plague extended in different directions at varying intervals. 
If we trace the Erie Railroad westward, we shall find that 
beyond New Jersey there is no city for the space of 200 miles, 
and this, together with the fact that cattle could be drawm so 
much more cheaply from the west, has hitherto prevented the 
extension of pestilence westward. What few infected cattle have 
found their way west along the line of the Erie Railroad have 
gone upon enclosed farms, where the plague reached its limit and 
died out, in place of finding the malign conditions of unfenced 
grounds and pasturage in common, which would inevitably have 
perpetuated it. The non-infection of the west we owe not alone 
to the immense cattle traffic from the west, and the fact that 
comparatively few cattle follow a contrary course, but also to the 
barrier of the Alleghany Mountains, and the entire absence of 
large and growing towns and cities over a long stretch of 
country. 
If we follow the New York Central Railroad we find a similar 
comparative absence of large cities, but w r e find besides that the 
east bank of the Hudson is well fenced, so that though the 
Lung Plague had been introduced, it would have had less op¬ 
portunity for permanence than in the district south of New 
York. North of Yonkers, where the open pasturages end, the 
plague has never gained a permanent footing on the east bank of 
the Hudson. 
On the Harlem Railroad there is a similar absence of large 
cities and common open pasturages, and although the plague 
has extended on this line as far north as the borders of Dutchess 
Co., it has been more easy to deal with it than where there w r as a 
common grazing ground for different herds. Erom Mt. Yernon 
southward, however, the common pasturage was more or less in 
vogue, and with it the prevalence of the plague and the difficulty 
of dealing with it. 
Along the New Haven Railroad the condition of things was 
more favorable to the propagation of the plague, and it would 
have been certainly perpetuated in some of the cities of Connec¬ 
ticut, but that the State Cattle Disease Commission repeatedly 
interposed to stamp it out. 
Extinction of the Lung Plague in Massachusetts .—Into Mas¬ 
sachusetts the Lung Plague was introduced in 1S59 in the 
bodies of four Dutch cows imported from Rotterdam by Mr. 
Chenery, of Belmont. All four suffered from the disease, two 
having been very ill on arrival. Three died, the fourth re¬ 
covered, and the plague spread into nineteen towns in five 
counties, and was only crushed out after five years of uninter- 
