533 



SCIENTIFIC SIDE-LIGHTS 



Plasticity 

 Pledge 



stripped of its original purpose, and result- 

 ing in pleasurable emotion. WUNDT Psy- 

 chology, lect. 24, p. 357. (Son. & Co., 1896.) 



2629. PLAYHOUSES OF THE BOWER- 

 BIRD Love of the Beautiful Esthetic Sense 

 in Animals Stealing of Bright and Attract- 

 ive Objects. Some animals exhibit emo- 

 tions of the beautiful. The following is 

 Mr. Gould's description, in extenso, of 

 the habits of the bower-bird of New South 

 Wales : The extraordinary bower-like struc- 

 ture, alluded to in my remarks on the 

 genus, first came under my notice in the 

 Sydney Museum, to which an example had 

 been presented by Charles Cox, Esq. . . . 

 On visiting the cedar bushes of the Liver- 

 pool Range, I discovered several of these 

 bowers or playing-houses on the ground, 

 under the shelter of the branches of the 

 overhanging trees, in the most retired part 

 of the forest; they differed considerably in 

 size, some being a third larger than others. 

 The base consists of an extensive and rather 

 convex platform of sticks firmly inter- 

 woven, on the center of which the bower 

 itself is built. This, like the platform on 

 which it is placed, and with which it is in- 

 terwoven, is formed of sticks and twigs, but 

 of a more slender and flexible description, 

 the tips of the twigs being so arranged as to 

 curve inwards and nearly meet at the top ; in 

 the interior the materials are so placed that 

 the forks of the twigs are always presented 

 outwards, by which arrangement not the 

 slightest obstruction is offered to the pas- 

 sage of the birds. The interest of this curi- 

 ous bower is much enhanced by the manner 

 in which it is decorated with the most gaily 

 colored articles that can be collected, such as 

 the blue tail-feathers of the Rose-hill and 

 Pennantian parrakeets, bleached bones, and 

 shells of snails, etc.; some of the feathers 

 are inserted among the twigs, while others, 

 with the bones and shells, are strewed near 

 the entrances. The propensity of these birds 

 to fly off with any attractive object is so well 

 known to the natives that they always search 

 the runs for any small missing article that 

 may have been accidentally dropped in the 

 bush. I myself found at the entrance of 

 one of them a small, neatly worked stone 

 tomahawk of an inch and a half in length, 

 together with some slips of blue cotton rag, 

 which the birds had doubtless picked up at 

 a deserted encampment of the natives. RO- 

 MANES Animal Intelligence, ch. 10, p. 279. 

 (A., 1899.) 



2630. PLEASURE AND PAIN, EX- 

 PRESSION OF Tension or Relaxation of 

 Muscles. In this law of pleasure and pain 

 we have the key to the leading varieties of 

 expression of the feelings. The organs of 

 expression by movement are primarily the 

 features, next the voice, lastly the move- 

 ments and gestures of the body at large 

 head, trunk, and extremities. In pleasurable 

 emotions these are unquestionably rendered 

 active; the grimaces, gestures, and attitudes 



show an accession of active power. The 

 notable circumstances in this display are 

 the general erection of the body, the open- 

 ing up of the features, the powerful exer- 

 cise of the voice; all showing that the ex- 

 tensor muscles, which are by far the largest, 

 are strongly stimulated. When we have 

 surplus energy to expend we stretch and ex- 

 tend the body in preference to bending and 

 relaxing it; the weight of 4he body itself is 

 borne in the one case and not in the other. 

 Any additional strain, as in walking, lifting 

 weights, rowing a boat, is borne by the 

 extensor muscles. It is the size of these 

 that makes the muscular figure, the ful- 

 ness of the calves, the thighs, and the hips. 

 On the other hand, pain (not violently 

 acute), dejection, depression, leads to the 

 relaxation of all these powerful muscles; 

 hence a general stooping and collapse of the 

 figure, showing that the springs of muscular 

 force have dried up. The difference of the 

 two situations, as regards the carriage of 

 the whole body, is most marked. Compare 

 the victor in a triumph with one of his 

 captives the attitude of the beater with 

 the beaten. And as regards the face, how 

 much is suggested by the one descriptive 

 trait, "His countenance fell"! BAIN Mind 

 and Body, ch. 4, p. 17. (Hum., 1880.) 



2631. PLEASURE, STRANGE, IN 

 DESOLATION The Question of the Wilder- 

 ness. The plain as usual consisted of 

 gravel, mingled with soil resembling chalk 

 in appearance, but very different from it 

 in nature. From the softness of these ma- 

 terials it was worn into many gulleys. 

 There was not a tree, and, excepting the 

 guanaco, which stood on the hilltop, a 

 watchful sentinel over its herd, scarcely an 

 animal or a bird. All was stillness and 

 desolation. Yet in passing over these scenes, 

 without one bright object near, an ill-defined 

 but strong sense of pleasure is vividly ex- 

 cited. One asked how many ages the plain 

 had thus lasted, and how many more it was 

 doomed thus to continue. 



None can reply all seems eternal now. 

 The wilderness has a mysterious tongue, 

 Which teaches awful doubt. 



SHELLEY, Lines on Mont Blanc. 



DARWIN Naturalist's Voyage around the 

 World, ch. 8, p. 168. (A., 1898.) 



2632. PLEDGE, UTILITY OF A Strong 

 Initiative. In the acquisition of a new 

 habit or the leaving off of an old one, we 

 must take care to launch ourselves with as 

 strong and decided an initiative as possible. 

 Accumulate all the possible circumstances 

 which shall reenforce the right motives; put 

 yourself assiduously in conditions that en- 

 courage the new way; make engagements 

 incompatible with the old; take a public 

 pledge, if the case allows; in short, envelop 

 your resolution with every aid you know. 

 This will give your new beginning such a 

 momentum that the temptation to break 

 down will not occur as soon as it otherwise 



