574 



THE POPULAR SCIENCE MONTHLY. 



as much game as possible, which is to be 

 given to his father-in-law. The latter 

 dresses the meat and invites the whole 

 tribe to a feast. Then he and his family in 

 their turn go hunting, and present the game 

 they have obtained to the young man's fa- 

 ther, who gives a feast to the whole tribe. 

 At this time the girl's father returns all the 

 payments he has received to the young man's 

 father. For a number of days the couple 

 live with the girl's family. When the young 

 man goes to reside with his wife he asks all 

 his friends to support him, and they give 

 him presents of food and clothing. The lat- 

 ter he puts on, one suit on top of the other, 

 goes to his father-in-law, and gives him all 

 the ^ property he carries. The latter dis- 

 tributes this property among the whole 

 tribe according to the contributions every 

 one has made. Then the young couple re- 

 move to the young man's family ; and before 

 leaving her father's house the bride is fitted 

 out with presents in the same way as the 

 young man was when he came to reside with 

 her family. This is a present to the young 

 man's father, who also distributes it among 

 the tribe." 



Some Cliaracteristics of Waves. — The 



friction of the wind upon the sea-surface, 

 the convulsions of deep-seated earthquakes, 

 and the attraction of the heavenly bodies, 

 give rise to three different kinds of sea- 

 waves. If the wind blows directly parallel 

 to the sea-surface, says a writer in Cham- 

 bers's Journal, the friction may cause an 

 ocean - current without wave - disturbance. 

 As a rule the direction of the wind is in- 

 clined to the sea-surface, and its immediate 

 effect is to produce a depression, which re- 

 lieves itself by means of a wave to leeward 

 and another to windward. This latter ele- 

 vation is opposed by the wind, and gradu- 

 ally dies away, while the leeward wave is 

 correspondingly accelerated. Each undula- 

 tion shelters the water under its lee from 

 the wind, which consequently impinges up- 

 on the sea a little in advance of the newly 

 formed wave ; and thus we get a series of 

 parallel ridges and hollows, provided the 

 wind remain steady in direction and inten- 

 sity. There is no necessary connection be- 

 tween the advance of a wave and the for. 

 ward movement of the water composing it, 



as may be seen by running the fingers along 

 the keys of a piano. An inverted ware 

 travels along, but the keys merely move up 

 and down. Similarly, a wave may often be 

 observed running along the ripe ears of 

 golden grain ■while the stalks are firmly 

 rooted in the soil. The onward progress of 

 a sea-wave is easily perceptible, and by watch- 

 ing some light substance floating on the sur- 

 face the fact is revealed that the water is 

 not moving with the same velocity as the 

 advancing wave. Should the wind direction 

 suddenly change, a new series of waves will 

 be generated, and cross -seas soon confront 

 the mariner. Hence it is that in a cyclone, 

 or revolving storm, where the wind is fre- 

 quently changing, there are high waves roll- 

 ing along from various directions, each as 

 distinct as the ripples in a river, which cross 

 one another without swerving from their 

 course. Waves become short and abrupt in 

 shallow water, and are far more dangerous 

 to shipping than the long, regular billows 

 of the ocean. It is probable that the great- 

 est slope of a wave in open waters does not 

 exceed thirty degrees, and frequently not 

 more than fifteen degrees. Waves raised 

 by the friction of the wind upon the water 

 are relatively superficial. In heavy gales, 

 however, lower depths become troubled, and 

 the undulations more and more imposing. 

 Occasionally an exceptionally large solitary 

 wave is met with, advancing in awe-inspir- 

 ing grandeur, its white crest towering high 

 above all its fellows. Such ocean giants may 

 be due to the fact that the elevations of se- 

 ries of waves having different lengths hap- 

 pen to coincide ; or may be caused by squalls 

 of wind, which are sometimes as terrible in 

 intensity as they are sudden in formation. 



The Wagging of the Dog's Tall.— Prof. 



Eimer, in his work on Organic Evolution, is 

 not able to explain why the dogs of Constan- 

 tinople erect the tail and carry it upright, 

 while the ancestral wolf and the jackal 

 carry it hanging down. Dr. Joseph L. Han- 

 cock suggests, in the American Naturalist, 

 that the reason may be found in the fact 

 that as the dog becomes domesticated it is 

 prone to use the tail as an organ for express- 

 ing mental states — wagging it when pleased, 

 dropping it between the legs when disap- 

 pointed or frightened. The ancestral wolf 



