officers had wine." Thus in the drinking-water no difference obtained. Ballast might have been a vehicle of infection, and for this purpose sea-sand and shingles, and other material, were taken from the shore. But I have been informed that "on the Britannia, as well as other English men-of-war, the ballast consisted only of so-called pig-iron, four-sided pieces, which were wedged together in the lowest part of the vessel, and never touched." We have yet to consider the different habits of the men and the officers while on shore before the outbreak of the epidemic. On this matter my informant writes: "The sufferers, not only of the Britannia, but of the rest of the ships of the fleet, had frequent communication by daily visits with the shore as we lay off Varna, and the crew without doubt betook themselves to those poisonous liquors, and still worse places of pleasure, which had sprung up on shore like mushrooms." It may be understood that the company of one ship would, like men of the same regiment, visit places of pleasure together and imbibe the same drink, and so it might happen that a particular crew visited a certain place where cholera prevailed, while other crews might have unconsciously kept clear of the places from which it is supposed cholera was taken. It remains doubtful whether the infection was derived through the air, water, or food. If these circumstances be viewed in an unprejudiced light, it will be seen that local conditions may account for the infection and spread of cholera on board ships. On emigrant-ships the matter can not be otherwise, and it is necessary, therefore, to inquire into the previous history of those who were taken ill on board. I have shown that the eleven cases of cholera which occurred on the Westphalia, bound for New York from Hamburg, came exclusively from two German families, and that an epidemic as vast as that which befell the crew of the Britannia might be explained, if we supposed that a majority of it came from the same district, or were placed under the same conditions as the two German families prior to their going on board. The exceptional outbreaks on emigrant-ships prove that such an occurrence is possible. That the Britannia, as a ship, was not a place of infection, is shown by the freedom from cholera enjoyed by the sixty officers. These points may possibly be cleared up by the appointment of a commission to inquire into the presence and etiological factors of cholera on board ship during epidemics of cholera. Koch has spoken of the occurrence of cholera on ships, and has attempted to reconcile matters on the basis of his doctrines of contagion. He has studied those ships which ply between North America and Calcutta. This line has not escaped my attention, and I have stated the main facts in my paper on "Cholera in India," 1871. Koch comes to the same conclusions as I did. Of two hundred and twenty-two vessels which made the voyage during ten years, cases of cholera only appeared on thirty-three ships, although they started from a district where cholera is endemic. It appeared to Koch only to be of importance, that cases of cholera continued to occur more than
