December 31, 1886.] 



SCIENCE. 



621 



but they roust be taken in a certain way to war- 

 rant definite conclusions. From the facts that 

 more cases of insanity are now treated, that we 

 have more asylums, and that our age is called a 

 neurotic one, the mournful conclusion is drawn 

 that a greater proportion of civilized humanity is 

 succumbing to the stringent requirements of mod- 

 ern life, and losing its mental equilibrium. Dr. 

 Tuke shows, that, by such statistics, the insane of 

 the past thirty years or so, whose lives our im- 

 proved methods of treatment have succeeded in 

 prolonging, are pushed upon our shoulders. The 

 real test of the prevalence of insanity is the pro- 

 portion of first attacks occurring witliin certain 

 periods. On this basis, Dr. Tuke shows that since 

 1878 (the earliest date from which adequate statis- 

 tics exist) there is no increase in occurring insan- 

 ity in Great Britain. On the whole, there is a 

 slight tendency to decrease ; and this, too, though 

 cases are now more apt than ever to be brought to 

 notice. 01 course, this should not lessen our vigi- 

 lance in the matter, nor remove our attention 

 from that large class on the borderland of insanity 

 which is not recorded, and from which any sud- 

 den crisis chooses its victims. 



The physiology of digestion has been so 

 thoroughly investigated of late years, that it 

 would seem that there could be very little oppor- 

 tunity for difference of opinion on most of its 

 leading principles, and yet we find that authori- 

 ties are on some points very much at variance. 

 We are told that nothing can be more prejudicial 

 than the habit of chewing gum, supposed to be so 

 common among school -children. The salivary 

 glands ai'e unnaturally excited, and pour forth 

 so much saliva in the act, that when food is 

 masticated they are not able to respond as fully 

 as is necessary for the proper insalivation of the 

 food. We are also informed that food should not 

 be eaten just before retiring; that thoroughly re- 

 freshing sleep requires perfect repose of all the 

 organs ; and that, if we go to sleep with a more or 

 less full stomach, sleep will be disturbed and un- 

 satisfactory. The authorities of Amherst college 

 evidently do not agree with these views. In the 

 instructions which they give to their students to 

 guide them in their gymnastic exercises, after 

 specifying the kind and amount of physical exer- 

 cise, they recommend sleeping for half an hour 

 after dinner and supper if possible, and, if sleep- 

 less at night from brain-work, to eat a few graham 

 crackers before retiring, to draw the excess of 



blood from the brain to the stomach. In reference 

 to the practice of chewing gum, this statement is 

 made : chewing gum daily before eating and be- 

 tween meals increases the flow of saliva, and so 

 aids the digestion of fat-making foods. It also 

 indh-ectly stimulates the secretion of the digestive 

 juices of the stomach. We have no means of 

 knowing, but we presume that Professor Hitch- 

 cock of Amherst, who is himself a physician, is 

 largely responsible for this advice, and have no 

 doubt that he has given it after mature considera- 

 tion. We fully agree with what is said in the in- 

 structions about the usefulness of food in cases of 

 sleeplessness, and believe that many a person has 

 been kept awake at night from a mistaken idea of 

 the necessity of abstemiousness before retiring. 

 This, of course, does not mean that late suppers 

 are under all circumstances to be recommended ; 

 but a few graham crackers can never do harm, 

 and will often do good. In regard to the chewing- 

 gum, we do not feel so sure. Besides being a 

 practice which is from an aesthetic point of view 

 not to be encouraged, it is very doubtful whether, 

 under the most favorable circumstances, it is 

 really a benefit to digestion ; and, until there is 

 some guaranty as to the composition of what is 

 called chewing-gum, we should hesitate before 

 recommending it in such unqualified terms. 



A FULL account of the Union Pacific railroad 

 weather-service has been furnished to the news- 

 papers in the west by Lieutenant Powell of the 

 signal service, who is in charge of the new enter- 

 prise, and now engaged in bringing ii into shape 

 for practical work. There will be thirty-three 

 stations in all. It is proposed to issue predictions 

 twice a day, announcing the expected weather 

 changes from twenty-four to forty-eight hours 

 beforehand. This will give the raihoad officials 

 ample time before the trains start in the after- 

 noon and morning to make any changes which 

 the predicted weather may necessitate. The 

 predictions will be couched in specific lan- 

 guage, and not in meaningless general terms. 

 For instance : one indication will predict in a 

 certain division cold weather with snow, the 

 wind being from the north and blowing at the 

 rate of thirty miles an hour, followed by warmer 

 weather, the wind changing to a southerly direc- 

 tion. Study of the road will determine where 

 the worst snow-drifts most frequently occur, and 

 from this it will be possible to tell pretty nearly 

 where snow blockades are liable to form. An accu- 



