R M. Bach€ on ^ea-sickii 



(Read before the Connecticut Academy of Arts and Sciences, January 15,*1863.) 



All that is known about sea-sickness is, that certain involun- 

 tary motions of the body produce an effect upon the nervous sys- 

 tem. This effect results in nausea. This nausea is called sea-sick- 

 ness. The question is not solved, as to the manner in which the 

 nervous impression is produced. 



It is generally supposed, that sea-sickness is produced by the 

 mere motion of the body, and consequently of the stomach. 

 That it is produced by motion, is not to be denied, but as wher- 

 ever sea-sickness occurs, motion is the pervading concomitant 

 of existence— the thing most patent of all that is evident to the 

 senses, and the body is so unpleasantly subjected to it, we lose 

 sight of the fact, that with the body are also subjected all the 

 senses or perceptive faculties, and that these are called upon 

 to comprehend an entirely novel state of existence. 



I have said, that the mere action of motion upon the body is 

 supposed to produce the nausea called sea-sickness. I hope to 

 be able to overthrow this theory by the arguments and proofs of 

 another theory, which I am about to advance. 



The points which I intend to prove are— that the agreeable- 

 ness of motion is a mere matter of habit— that motion however 

 violent is not nauseating "perse" but only inasmuch as it pro- 

 duces an impression conflicting with its ordinary contrasted 

 effects as pre-established in the mind, that the idea of motion is 

 the result of concurrent testimony of the senses— and, that in 

 novel motions, there is a violation of the conception of motion 

 derived from the habitual concurrence of the testimony of the 

 senses— that as the result of this violation, a conflict of impres- 

 sions ensues, and the brain is affected— thence the nervous sys- 

 tem, and nausea results. In fine, I maintain that sea-sickness is 

 a disease of the brain, and not of the stomach, except incident- 

 ally, or as affected by the brain, although, it is true, that the 

 stomach reacts upon the brain. 



I now commence my argument in which I have attempted a 

 procedure, which, I trust, cannot fail to bring conviction of the 

 truth of the theory to any one who will carefully analyze it. 

 In all statements of facts which I have introduced I have taken 

 the experience of others, as well as my own. 



The appearance of motion when the observer knows that his 

 own body is at rest, is not nauseating. To ascertain the effect of 

 the mere appearance of motion under these circumstances, we 

 can take no better example, than that of a train of cars drawn 

 by a locomotive at full speed. The more rapid motions of the 

 Am. Jouk. Sci.— Secoxd Sebim, Vol. XXXIV, No. 100.— Jijlt, 1862. 



