43° 



POPULAR SCIENCE MONTHLY. 



more simple and regular, says Captain W. J. 

 L. Wharton, than in the British Isles, in re- 

 markable contrast to the opposite American 

 coast, where it is very complicated. The 

 minor tides, which in most parts of the world 

 considerably affect the volume of the whole, 

 are in Great Britain comparatively insignifi- 

 cant ; why, is not yet explained. Some curi- 

 ous interference phenomena originating in 

 the meeting of tidal waves from opposite 

 directions, or in rebounds from the coasts, 

 have been observed in the British Isles. 

 The tidal range of about fifteen feet on the 

 western part of the southern coast of Eng- 

 land diminishes as we go eastward to one of 

 six feet near Poole, then increases to Hast- 

 ings, where it is twenty-four feet, and then, 

 farther east, gradually diminishes. This is 

 due to reflection from the French shores, 

 which brings waves that here re- en force, 

 there reduce, the main wave, according to 

 details so complex that they have not yet 

 been studied out. Variations in the mean 

 range of tides on many coasts may be ac- 

 counted for as resulting from such reflections, 

 which may come from longer distances and 

 be more numerous than we are now aware of. 



Toads at Dinner. — The toad does not 

 take dead or motionless food. Only living 

 and moving insects, centipeds, etc., are de- 

 voured, while worms or other larvae disturbed 

 by their hopping are safe so long as they re- 

 main curled up ; but as soon as they move 

 they are captured. The toad's tongue, its 

 only organ for seizing food, is soft, extensile, 

 attached in front but free behind, and is 

 covered witli a glutinous substance that ad- 

 heres firmly to the food seized. So rapid is 

 the motion of this weapon that a careful 

 watch is necessary in order to see the animal 

 feed. At night, soon after sunset or even 

 before on cool evenings, the toad emerges 

 from its shelter and slowly hops about in 

 search of food. Something of a regular beat 

 is covered by these animals, whose sense of 

 locality is strong. In the country this beat 

 includes forage along the roadside, into gar- 

 dens and cultivated fields, and wherever in- 

 sect food is abundant and grass or other 

 thick herbage does not interfere with getting 

 about. In cities and suburban villages the 

 lawns, walks, and spots beneath the electric 

 lamp3 are favorite hunting grounds. At Am- 



herst, Map s., Mr. A. H. Kirkland, from whose 

 paper we derive these observations, once 

 counted eight large, well-fed toads seated 

 under an arc light and actively engaged in 

 devouring the insects which, deprived of 

 wings, fell from the lamp above. At Mai- 

 den, Mass., a colony of about half a dozen 

 toads sally forth on summer evenings from 

 under the piazza of a citizen's house, go 

 down the walk, cross the street, and take up 

 their stations under the arc lamp, where they 

 feed upon the fallen insects till the current 

 is turned off, when they return to their ac- 

 customed shelter. 



Unexplored Regions in Asia.— In the com- 

 ing century there will be abundance of work 

 for explorers in Asia, said Dr. J. Scott Keltie 

 in the British Association, and plenty of ma- 

 terial to occupy attention. They lie in two 

 separate regions. In southern and central 

 Arabia there are tracts which are entirely 

 unexplored. These regions are probably a 

 sandy desert. At the same time they are, 

 in the south at least, fringed by a border of 

 mountains, whose slopes are capable of rich 

 cultivation, and whose summits the late Mr. 

 Theodore Bent found to be covered with snow. 

 If any traveler cared to face the difficulties, 

 physical, political, and religious, which would 

 probably be met with, he might be able to 

 tell the world a surprising story. Another 

 region in Asia where real pioneer work still 

 remains to be done is Tibet and the moun- 

 tainous districts bordering it on the north 

 and east. Lines of exploration have in recent 

 years been run across Tibet by Russian expe- 

 ditions like that of Prejevalsky, by Rockhill, 

 Prince Henry of Orleans, Bonvalot, Bower, 

 Littledale, Wellby, and Malcolm. From the 

 results obtained by these explorers we have 

 formed a fair idea of this, the most exten- 

 sive, the highest, and the most inhospitable 

 plateau in the world The forbidden city of 

 Lassa is at present the goal of several ad- 

 venturers, although as a matter of fact we 

 can not have much to learn in addition to 

 what has been revealed in the narrative of 

 the native Indian traveler, Chandra Das. The 

 magnificent mountain region to the north and 

 east of Tibet furnishes a splendid field for 

 the enterprising explorer. Then there are 

 the series of parallel mountain chains south- 

 east of Tibet through which the upper waters 



