Page:Popular Science Monthly Volume 46.djvu/736

718 of getting at the truth. He is especially liable to be led away by impatience to get results. Preliminary communications are a very great as well as a very prevalent evil. The greed for priority leads many even fine workers far astray. The tendency to speculate is a third evil, and a fourth is the disposition to accept too readily simple and well-finished conceptions. It is the function of original memoirs to assimilate crude facts and render them digestible. Details not bearing directly on the subject should be carefully excluded. Most original papers could be "boiled down" to one half and some even to one tenth of the amount that is really published. The effect of the work of the naturalist upon his own character is best shown by his optimism. One drawback in the naturalist's life is his comparative loneliness and isolation. Seldom has he in his own neighborhood another interested in the same particular line as himself. Reunions of naturalist societies counteract this to a considerable extent, but there is need of even greater affiliation. Naturalists should exercise influence in teaching men competence. The solution of our present political troubles lies not so much in restricting the right to vote as it does in restricting the right to be a candidate. We, as naturalists and as citizens, should uphold competence. The naturalist should see that the schools educate, with science in its proper place.

The Senses of Plants.—The conclusion is reached by J. C. Arthur in a president's address before the Indiana Academy of Science on The Special Senses of Plants, that plants seem to react sensitively to gravity, light, moisture, heat, and contact. Each is a special kind of sensitiveness having its own method of reaction. Two or more kinds of sensitiveness may reside in the same organ, when its position will be a resultant of the several forces. There are consequently no exclusive organs of sense, although there is more or less localization in certain parts, and there are no nerves, although the motor impulse may be transmitted some distance, even so far as twenty inches or more in very vigorous Sensitive Plants—that is, in Mimosa. There are also no muscles in plants, although they execute movements of very considerable amplitude. The real mechanism by which the movements are accomplished is not well understood. There is agreement, however, in assuming it to be due to the movement of water. All the senses, except that of contact, have for their end the adjustment of the plant as a whole, and of each of its organs, in a suitable position for heat development. The contact sense has been more variably developed, aiding the plant to climb, to catch insects for food, and, if we are to accept Darwin's suggestion, enabling the Sensitive Plant in particular to escape the injury of hailstones. All the movements are very slow, except a few like insect-catching and hail-avoiding movements, and their wonderful diversity and extent are realized only by instituting carefully devised experiments and the use of delicate instruments. It is to be noted that the same organ always responds to the same stimulus with the same corresponding movement. There is no opportunity for choice, no volition, and consequently no mental activity, no psychic life of even the most humble and rudimentary nature.

Characteristics of Maps.—Maps, said Dr. R. H. Mill, in a lecture on Holiday Geography at the Royal Geographical Society's rooms, may be viewed as a kind of shorthand, and are easier to read than books. Far more information is given in a map than could be written or printed upon a piece of paper of equal size, and a map could point out to several persons coming from different directions the way to a certain place, since it does not introduce the confusing notices of right and left, as verbal instructions do. In Aberdeen the confusion is avoided, because there a man is told to go north or south instead of to the right or left; and it is even said that in some places in Scotland the position of the dishes on the table is regulated by the same principle. The value of maps depends on their purpose and their accuracy. A map that had been taken from a tramp, exhibited to the audience, though worthless for the measurement of distances, was very valuable to the beggar, since all the houses were marked upon it, and the character of their inhabitants, together with the presence of dogs, were indicated by peculiar signs. In a number of old pictorial maps various strange animals were seen disporting