igacity 

 ivajrery 



SCIENTIFIC SIDE-LIGHTS 



596 



unattended by danger, and these animals 

 are often observed to have been lamed by 

 the puncture of the cactus thorn. HUM- 

 BOLDT Views of Nature, p. 15. (Bell, 1896.) 



2945. SAGACITY OF A WASP- Cut- 

 ting Bulky Prey into Manageable Parcels. 

 Dr. Erasmus Darwin records an observation 

 ("Zoonomia," i, p. 183) which, from having 

 since been so widely quoted, deserves to be 

 called classical. He saw a wasp upon the 

 ground endeavoring to remove a large fly 

 which was too heavy for it to carry off. The 

 wasp cut off the head and abdomen, and flew 

 away with the thorax alone. The wind, 

 however, catching the wings of this portion 

 made it still too unwieldy for the wasp to 

 guide. It therefore again alighted and 

 nipped off first one wing and then the other, 

 when it was able to fly off with its booty 

 without further difficulty. This observation 

 has since been amply confirmed. ROMANES 

 Animal Intelligence, ch. 4, p. 195. (A., 1899.) 



2946. SAGACITY OF ESKIMO DOGS 



The Pack Scattering When on Thin Ice, 

 to Distribute Their Weight. It will be re- 

 membered in connection with these dogs 

 that Mr. Darwin in the " Descent of Man " 

 (p. 75) quotes Dr. Hayes, who, in his work 

 on " The Open Polar Sea," " repeatedly re- 

 marks that his dogs, instead of continuing 

 to draw the sledges in a compact body, di- 

 verged and separated when they came to 

 thin ice, so that their weight might be more 

 evenly [and widely] distributed. This was 

 often the first warning which the travelers 

 received that the ice was becoming thin and 

 dangerous." Mr. Darwin remarks : " This 

 instinct may possibly have arisen since the 

 time, long ago, when dogs were first em- 

 ployed by the natives in drawing their 

 sledges; or the Arctic wolves, the parent 

 stock of the Eskimo dog, may have ac- 

 quired an instinct impelling them not to 

 attack their prey in a close pack when on 

 thin ice." ROMANES Animal Intelligence, 

 ch. 16, p. 462. (A., 1899.) 



2947. SAGACITY SURPASSES THE- 

 ORY Regelation of Ice and Snow. Two frag- 

 ments of ordinary table ice brought care- 

 fully together freeze and cement themselves 

 at their place of junction; or if two pieces 

 floating in water be brought together, they 

 instantly freeze, and by laying hold of 

 either of them gently you can drag the 

 other after it through the water. Imagine 

 such points of attachment distributed in 

 great numbers through a mass of snow. 

 The substance becomes thereby a semisolid 

 instead of a mass of powder. My guide, 

 however, unaided by any theory, did a thing 

 from which I should have shrunk, tho 

 backed by all the theories in the world 

 [viz., tramping Alpine snow into a firm 

 support]. TYNDALL Hours of Exercise in the 

 Alps, ch. 9, p. 100. (A., 1898.) 



2948. SALT A NECESSITY OF LIFE 



Common salt . . . is an article of food, 



tho often miscalled a condiment. Salt is 

 food simply because it supplies the blood 

 with one of its normal and necessary con- 

 stituents, chlorid of sodium, without which 

 we cannot live. A certain quantity of it 

 exists in most of our ordinary food, but not 

 always sufficient. WILLIAMS Chemistry of 

 Cookery, ch. 15, p. 259. (A., 1900.) 



2949. SALVATION AN ACTIVE, EF- 

 FECTIVE PRINCIPLE The Definitive Over- 

 coming of the Law of Deterioration and 

 Death. There is a natural principle in 

 man, lowering him, deadening him, pulling 

 him down by inches to the mere animal 

 plane, blinding reason, searing conscience, 

 paralyzing will. This is the active destroy- 

 ing principle, or sin. Now to counteract 

 this God has discovered to us another prin- 

 ciple which will stop this drifting process 

 in the soul, steer it round, and make it 

 drift the other way. This is the active sa- 

 ving principle, or salvation. To neglect it 

 is to cut off the only possible chance of 

 escape. In declining this he is simply aban- 

 doning himself with his eyes open to that 

 other and terrible energy which is already 

 there, and which, in the natural course of 

 things, is bearing him every moment fur- 

 ther and further from escape. DBUMMOND 

 Natural Law in the Spiritual World, essay 

 2, p. 96. (H. Al.) 



2950. SAND A PRESERVER OF AN- 

 CIENT MONUMENTS No mode of inter- 

 ment can be conceived more favorable to 

 the conservation of monuments for indefi- 

 nite periods than that now so common in 

 the region immediately westward of the 

 Nile. The sand which surrounded and filled 

 the great temple of Ipsambul, first discov- 

 ered by Burckhardt, and afterwards par- 

 tially uncovered by Belzoni and Beechey, 

 was so fine as to resemble a fluid when put 

 in motion. Neither the features of the 

 colossal figures, nor the color of the stucco 

 with which some were covered, nor the 

 paintings on the walls, had received any in- 

 jury from being enveloped for ages in this 

 dry impalpable dust. LYELL Principles of 

 Geology, ch. 45, p. 726. (A., 1854.) 



2951. SAND-BAR SHIFTED BY 

 STORM It sometimes happens that dur- 

 ing a violent storm a large bar of sand is 

 suddenly made to shift its position, so as to 

 prevent the free influx of the tides, or efflux 

 of river water. Thus about the year 1500 

 the sands at Bayonne were suddenly thrown 

 across the mouth of the Adour. That river, 

 flowing back upon itself, soon forced a pas- 

 sage to the northward along the sandy plain 

 of Capbreton till at last it reached the sea 

 at Boucau, at the distance of seven leagues 

 from the point where it had formerly en- 

 tered. It was not till the year 1579 that 

 the celebrated architect Louis de Foix un- 

 dertook, at the desire of Henry III., to re- 

 open the ancient channel, which he at last 



