Page:Popular Science Monthly Volume 9.djvu/660

634 not occur with any other kind of sewing. The case having now come under the notice of M. Bouchut, he gave the girl a buttonhole to sew. She had hardly sewn three stitches when she sank from her chair on the ground, and fell fast asleep. M. Bouchut raised her up, and noted catalepsy of the arms and legs, dilatation of the pupil, slowness of pulse, and complete insensibility. She slept for three hours. Next day he made a similar experiment, when the girl slept only one hour. While no other kind of sewing could affect the girl in this way, M. Bouchut found that he could produce hypnotism by causing her to look intently on a silver pencil held at the distance of ten centimetres from the root of her nose. The case evidently was one of Braid's hypnotism, only occurring spontaneously, and not brought on by way of experiment.

Periodic Movements of the Foliage of Plants.—The Abies Nordmanniana, a coniferous tree now widely diffused on account of the elegant coloration of its leaves, appears to bear uniformly whitish foliage, when observed in the morning or toward evening, but when observed in the middle of the day the green tint seems general. The reason of this difference is found in the fact that the position of the leaves on the branch is different in the daytime from what it is at night; in the former case the leaves are spread out upon the branch and present their upper surface, producing the greenish aspect of the foliage; during the latter period, on the contrary, it is the lower or whitish surface that is presented to the observer. Thus there is a diurnal and a nocturnal position. As the day declines, the leaves, which at noon were horizontal, are seen gradually to erect themselves upon the branch, often becoming nearly perpendicular to it, and this movement of erection is accompanied by a movement of torsion in the basal part of the leaf, often traversing an arc of 90°.

Treatment of Lunatics by Colored Light.—Medical journals give an account of experiments recently made by Dr. Ponza, director of the lunatic asylum at Alessandria, Piedmont, to determine the influence of the solar rays on brain-diseases. Dr. Ponza, having communicated his views to Father Secchi, was encouraged to study the subject. In his letter to Dr. Ponza, the Roman astronomer expressed the opinion that the violet rays are of special importance. "Violet," he writes, "has something melancholy and depressive about it; perhaps violet light may calm the nervous excitement of maniacs." He then advises Dr. Ponza to perform his experiments in rooms with stained-glass windows, and with the walls painted of the same color as the glass panes. One patient, who had been affected with morbid taciturnity, became gay and affable after spending three hours in a red chamber; another, a maniac who refused all food, asked for breakfast after having staid twenty-four hours in the same red chamber. In a blue chamber a highly-excited madman became calm in one hour. A patient was made to pass the night in a violet chamber; on the following day he felt himself cured, and has been very well ever since.

Unhealthy Trades.—Among the lectures delivered by Dr. Richardson before the London Society of Arts, on "Unhealthy Trades," is one devoted to the "Industrial Diseases of Workers in Earthenware." He shows from the official statistics that potters are among the three sections of the population of England who represent the lowest vitality. The males of fifteen years and upward die at the rate of 38 per cent, above the males of all ages; and the commencement of this increased mortality is at the period when the men are approaching their prime of life, namely, at thirty-five years, and it extends onward to the end of life. Thus where in the general population 100 males of thirty-five years die, a proportion equal to 154 potters dies. For the four subsequent increments, namely, forty-five, fifty-five, sixty-five, and seventy-five years, for 100 deaths in the general male population, the deaths among male potters are proportionately 182, 181, 192, 141. The wages of the potters are good, and the labor not physically severe on healthy, fully-developed persons. The special diseases incident to this kind of employment are bronchitis with "potter's asthma," pulmonary consumption, and lead paralysis. Subsidiary to these are rheumatic affections and affections of the stomach. The special causes of disease