Page:Popular Science Monthly Volume 10.djvu/127

Rh which represent the eyelids. The action of light on the disk is indicated on the galvanometer. Not only was this shown to be sensitive to white light, but sensitive in different degrees to different colors. Mr. Siemens suggested it would not be difficult to arrange a contact and electro-magnet in connection with the galvanometer in such a manner that a powerful action of light would cause the automatic closing of the eyelids, and thus imitate the spontaneous brain-action of blinking the eyelids in consequence of a flash of light. To physiologists this analogy may be suggestive regarding the important natural functions of the human frame.

Effect of Alcohol on Brain-Substance.—When brain-substance is placed in alcohol, it loses its water and its mobility of particles, and becomes more solid and firm. The question here arises, Is this thing possible with the living brain? Is it possible that, in cases of delirium tremens, so much alcohol has been consumed as, by its diffusion through the brain, it has robbed nerve matter of its mobile character, and consequently of its power to throw off the products of its life-functions? That alcohol may, in this way, act upon the brain of the inebriate, is an opinion which, as yet, can hardly be demonstrated directly; but an experiment made by Mr. Charles T. Kingzett seems to render it highly probable. He places in a dilute solution of alcohol pieces of brain-substance derived from the ox, at the temperature of the blood, viz., 100° Fahr. At this temperature it is digested for some hours, and the liquid is then filtered. On cooling, the filtrate throws down a white deposit of matter which the alcohol has dissolved—a phenomenon which would seem to indicate some actual truth in Shakespeare's words, "O that men should put an enemy in their mouths to steal away their brains!"

Foray of an Army of Ants.—A writer in Land and Water gives an interesting account of a foray by an army of ants, which he witnessed in South Africa. This army, estimated to number about 14,000 ants, started from their home in the mud walls of a hut, and marched out in the direction of a small mound of fresh earth in the vicinity. The head of the column halted on reaching the foot of the mound, and the remainder of the force did likewise till the entire army was assembled. Then the forces were divided: one part remained at the foot of the mound and ran round and round it; the rest mounted to the top, and some of them entered the loose earth and speedily returned, each bearing a young grasshopper or cricket, dead, which he deposited upon the ground and returned for a fresh load. Those who had remained on the outside of the mound took up the crickets as they were brought out of the earth, and bore them down to the base of the hill, returning for a fresh load. Soon the contents of the mound seemed to be exhausted, and then the whole force returned home, each carrying his burden of food for the community. Here was a regular foray, planned and executed with military precision, the country surveyed, and the depot of provisions known accurately before the march was made; at the mound, prudential division of labor, and care taken that none of the victims should escape.

Remedy for Cold in the Head.—Dr. David Ferrier, having used with great success trisnitrate of bismuth to cure "cold in the head," sends to the Lancet a communication in which he warmly commends the employment of bismuth, either alone or in conjunction with other drugs, in the treatment of nasal catarrh. Bismuth of itself being heavy, and difficult to inhale, it is advisable, he writes, to combine it with acacia-powder, which increases the bulk, and renders the powder more easily inhaled, while the secretion of the nostrils causes the formation of an adherent mucilaginous coating, of itself a great sedative of an irritated surface. The sedative effect is greatly strengthened by the addition of hydrochlorate of morphia, which speedily allays the feeling of irritation and aids in stopping the reflex secretion of tears. He proposes the following formula: Hydrochlorate of morphia, two grains; acacia-powder, two drachms; trinitrate of bismuth, six drachms. Of this powder one-quarter or one-half may be taken as snuff in the course of twenty-four hours. The inhalations should be commenced as soon as the