Cruise seasickness

Cruise seasicknessOptical vertigo is a variable quantity in the constitution of sea-sickness. With some it is the chief item. This is the case with a distinguished American who on a late voyage told me that his sea-sickness almost subsides and he can get about the deck quite well when night comes on. To exclude optical vertigo the eyes, of course, are to be kept closed.

Some have regarded sea-sickness as consisting entirely of optical vertigo, asserting that blind persons do not get sea-sick. Instances enough of blind persons getting sea-sick are, however, cited in the literature of the subject; and I have made the subject a matter of personal inquiry of ship officers and at two institutions for the blind. I find that blind persons do get decidedly sea-sick.

There is probably not a class of ills known to doctors from which there are not some persons exempt, even when subjected to the severest tests. About one in two hundred of the human family are exempt from seasickness. This includes those only who are in good health and not sick when for the first time on the sea and subjected to the severest test for a sufficient length of time. This one in two hundred does not include young children. Any illness, however slight and in whatsoever way manifested to the subject, if it supervene in consequence of subjection to third class motion, or any condition present on and peculiar to the ship, is sea-sickness. Vomiting is not an essential symptom.

That severally and collectively the factors in the causation of sea-sickness produce different effects on different persons at the same time, and different effects on the same person at different times, is not more mysterious than the similar behavior of the causes of many other diseases.

Personally I have not been able to familiarize myself with a sufficient number of these exempts to see if there is anything in their constitution by which to account for their exemption. In the sequence of events which begins with motion and ends with sickness an essential item, we have seen, is a disappointment. Some exempts, whose mental constitutions I have attempted to scrutinize, have told me that they do not suffer violence even from such mental effects as are incidental to violent misfortunes. If in these cases there is no disappointment with its consequent violence, because there is no fixedness of expectations, or for other reasons, and this peculiarity of the individual is for him general, then the cause of his exemption is obvious.