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tact with an environment which usually presents a high ratio of 
infection. 
Owing to the steadily increasing tourist traffic in the Pacific 
Arena, the large modern ocean-carrier is coming more and more 
into use between the "tourist ports" and the Orient. These great 
steamers bring large numbers of immigrants from the Orient, 
and also the bulk of the Oriental freight. 
Therefore the "tourist ports" are important in a quarantine 
sense on account of the hazard caused by the periodical arrival of 
the large ocean carriers bringing tourists, immigrants ,and freight 
direct from the Oriental disease centers. 
The North American ports, on the other hand, are as a rule re- 
markably free from infection with the quarantinable diseases, and 
one might be led to regard them as unimportant from a quaran- 
tine standpoint but for the fact that they are the trans-shipping 
points for the whole continent of North America, from the fur- 
thest limit of which transportation can be effected in five or six 
days by rail. 
This fact makes it possible for a person having been exposed in 
New York City to the infection of smallpox, a disease having an 
incubation period of from twelve to fourteen days, to reach Hono- 
lulu before the disease manifests itself. 
The Asiatic ports are naturally the most important points from 
which to expect infection from all of the quarantinable diseases 
save yellow fever. The Philippine Island ports on account of the 
rigid out-going quarantine operated from these points by the Pub- 
lic Health and Marine Hospital Service has never given special 
concern. 
The Japanese ports, despite the high order of quarantine and 
internal sanitation practiced in those places are dangerous on the 
whole, both by reason of their close proximity to China, and by 
the heavy traffic always existing between Japan and China on the 
one hand and Japan and the United States on the other. The 
Australasian ports, particularly Sydney, Melbourne and Auck- 
land, at least as far as plague is concerned, are practically in the 
same class with those of Japan. The South American ports are 
danger points of great importance on account of smallpox, yellow 
fever and plague prevailing in those places a greater part of the 
time. The Isthmian ports are destined, however, to be the points 
from which the infection of the Pacific Arena with yellow fever 
is most likely to occur. 
The Alaskan ports are in the same class with those of Man- 
churia and the Straits or Malay Peninsula Settlements, being only 
tributary to recognized Trans-Pacific routes. 
It will be seen from this general mention of the present and 
prospective trade in the Pacific Arena and its probable effect upon 
quarantine conditions, that practical and successful measures to 
meet said conditions must be operated upon a schematic system. 
This schematic system should be devised with a view to its being 
