body of men charged with the details of any system entailing great personal inconvenience and loss to travellers and merchants. Therefore, if the strength of the quarantine chain is to be measured by that of its weakest link, the chain must be weak indeed, as a very slight knowledge of human nature will lead us to suspect, and a very slight acquaintance with the working of quarantine as ordinarily practised will attest. Even if the utmost care, intelligence, and honesty succeed in excluding individuals actually suffering from cholera, or likely within a reasonable time to suffer from cholera, there is yet no guarantee that the germ of the disease may not be introduced. Koch and others have shown that sometimes the dejecta even of individuals apparently in good health and who have not suffered, or who may not subsequently suffer from choleraic disease, may yet contain, and for some time continue to contain, the cholera vibrio. In 271 fatal cases Greig found the vibrio in the gall-bladder, a situation favouring persistence in the event of recovery. During the epidemic of 1911, in Naples, 10 per cent, of healthy contacts had cholera vibrios in their stools and continued to pass them for three to five days. If the cholera vibrio be the germ of cholera, then such healthy, vibrio-bearing individuals may well suffice to start an epidemic. It is impossible, short of absolute and complete isolation, for any practicable system of quarantine to deal efficiently with such cases.
So far from ordinary quarantine proving a defence against cholera, it may actually increase the risk of an epidemic. This it does by fostering a false sense of security, and so leading to neglect of those well-proved guarantors of the public health— domestic, municipal, and personal cleanliness, and a pure water and food supply.
The system to which Great Britain apparently owed her immunity during recent epidemics on the continent of Europe is a practicable and, in civilized conditions, an efficient one. Under this system only ships which were carrying or which had recently carried cholera patients were detained; and even
