��POPULAR SCIENCE MONTHLY.
��taken to preserre the breed and to neutralize vai-iation as far as possible, so that the seed may " come true " ; on the other hand, when the variation does occur, the observation of the grower marks the change, and he either rejects the plant, manifesting it as a " rogue," if the change is undesirable, or takes care of it for further trial if the variation holds out promise of novelty or improvement. Where the ilowers lend themselves readily to cross- fertilization by means of insects, it is essen- tial, in order to maintain the purity of the offspring to, grow the several varieties at a very wide distance apart. Some apparently slight variations, which even to the trained botanist are hardly noticeable, may be of great value commercially; as, for instance, of two apparently almost identical varieties of wheat one may be much better able to resist mildew and diseases generally than another. Some, again, prove to be better adapted to certain soils or for some climates than others. Some are less liable to injury from predatory birds, and so on. So far we have been alluding to variations in the plant as grown from seed, but similar changes are observable in the ordinary buds, and garden- ers are not slow to take advantage of these variations. The field is one of great scien- tific as well as commercial interest, and a thoroughly equipped biologist would probably soon distance the ordinary gardener, who works by rule of hand, in producing and perpetuating valuable variations.
Some African War Customs. — When war comes to the Bondei people in Africa, the Rev G. Dale, missionary, says, the first who hears it climbs up to the top of the house and beats the drum with one band, calling the people to assemble there. A drum is beaten in every village as soon as another drum is heard. Everybody goes where the first drum was sounded, and the people cry war all over the country. All the women and children go into the forest with their property, taking especial pains to carry the basket containing the money and beads. The warriors take their weapons, put their amulets on their arms and neck and face, and adjust their ostrich plumes. Each one supposes that the charms will keep him safe, and have power, even if he is struck with a bullet, to prevent its entering him. Another
��charm consists in scarifying the man all down his arms and breast and back, after which, it is believed, no sword will cut into his body. The great doctors have a powder which they put into water, which the wari'iors drink. On approaching the seat of war the warriors assemble, when every one is smeared on the face with a cer- tain preparation and given medicine, and is licked by the fundi. Then they separate ; each band goes in its special direction, and the battle takes place. If they conquer they return together singing songs signifying, "As the Hshundu is a great bird and is accustomed to the mountains, so we are ac- customed to war" ; or, *' Come and live in our land. That yonder is glowing with the fire of burned villages. We are like the Masai " ; and entering the village they shout, "The land is at rest, till and eat ! " If a man has been killed, they return singing, " My millet has a limit, who has eaten it ? " — go to the house of the dead man, fire their guns, and take away the grass that slopes over the door — and so the wife knows that she is a widow. Then they go and tell the old folks. The man who has killed an enemy in battle performs a ceremony for seven days which includes climbing to the top of the house every morning, boasting, and naming the man he has killed. If the warriors are de- feated, they come back one by one, having hidden themselves. In case of victory the women greet the warriors with great joy, and shave, for the first time since their husbands went to war.
Paints for Iron. — A new study of paints for iron has led Herr Spennrath to the con- clusion that none of the metallic oxides en- tering into the composition of paints com- bines chemically with the oil. The drying of the paint is caused solely by the absorp- tion of oxygen by the oil, which is facilitated in a purely mechanical way by the presence of the oxide. The relative value of the oxides is very variable. Oxide of zinc, when used in outside work, swells rapidly to twice the original volume, in consequence of the ab- sorption of carbonic acid and the vapor of water. The red and white oxides of lead absorb sulphureted hydrogen and increase in volume. These substances are, however, good driers when they are pure. Carbon