Page:Popular Science Monthly Volume 52.djvu/884

862 find as a result of their inquiry that all current theories are speculative and inadequate; they offer several good suggestions for a further study of the subject, two of which are the use of the camera and phonograph as automatic registers. The most important result of the inquiry seems to be the setting forth of how little we know about this department of mental phenomena.

The Blue Jay's Food.—A recent inquiry by F. E. L. Beal, assistant of the United States Department of Agriculture, into the food of the blue jay resulted in some unexpected results. The bird is distributed over the whole of the United States east of the great plains, and has a bad reputation, being charged not only with habitually robbing the nests of smaller birds of their eggs and young, but also with being very destructive to the farmer's grain. Mr. Beal examined two hundred and ninety-two stomachs in all. The remains of a small bird were found in two of these and portions of eggshells in three. He found that vegetable stuff made up three quarters of the blue jay's food, a good share of which is nuts and mast and wild berries. Their insect food makes up about twenty-three per cent of the whole, and consists largely of noxious and destructive sorts. He concludes as follows: "The most striking point in the study of the food of the blue jay is the discrepancy between the testimony of field observers concerning the bird's nest-robbing proclivities and the results of stomach examinations. The accusations of eating eggs and young birds are certainly not sustained, and it is futile to attempt to reconcile the conflicting statements on this point, which must be left until more accurate observations have been made. In destroying insects the jay undoubtedly does much good. Most of the predaceous beetles which it eats do not feed on other insects to any great extent. On the other hand, it destroys some grasshoppers and caterpillars and many noxious beetles, such as scarabæids, click beetles, weevils, buprestids, chrysomelids, and tenebrionids. The blue jay gathers its fruit from Nature's orchard and vineyard, not from man's. Corn is the only vegetable food for which the farmer suffers any loss, and here the damage is small. In fact, the examination of nearly three hundred stomachs shows that the blue jay certainly does far more good than harm."



the result of some recently conducted experiments on feeding hogs, it is announced by the Cornell University experiment station that fully twenty-five per cent of the diseases which are supposed by the farmer to be hog cholera, or some other of the infectious diseases which attack hogs, are simply due to unhealthy food or foul surroundings. It was found, among other things, that the dishwater from hotels (which forms the basis of the ordinary swill fed about towns) was especially injurious when any of the powdered soaps had been used for dishwashing purposes, and a large number of deaths among several herds were traced to this cause. The amount of free alkali, over fifty per cent, which is present in these soap powders in the shape of sodium carbonate (ordinary washing soda) was found to be the dangerous substance.

it possible, asks a writer in the Revue Scientifique, "to affirm positively that any particular medicine is injurious or any treatment bad? Assuredly not; what we condemn to-day will be good to-morrow. Did not the Sorbonne condemn quinine, tartar emetic, and antimony as injurious medicines? It was the same with transfusion. Science is revolutionized every moment by new discoveries. A doctor practicing laparotomy thirty years ago as it is practiced now would have been regarded as guilty of imprudence; yet the operation is very easily performed, perhaps too readily. There was a time when to give more than a gramme and a half or two grammes of iodide of potassium would have been a great fault; now, eighteen and even twenty grammes are given. Twenty-five years ago some doctors and even academicians denied that smallpox was contagious."

in a recent number of Science, calls attention to a paper by the Marquis de Nadaillac on The End of the Human Race, and comments as follows: "Making anew the calculation of the increase of population as compared with the increase 