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THE POPULAR SCIENCE MONTHLY. 



outlines and other features, it is difficult to 

 see how they escaped the cutting action of 

 the sea-beach that must have been dragged 

 over all of this surface as it was emerging 

 from the sea. A single month of exposure 

 to such waves as act even in the more shel- 

 tered bays would entirely destroy their more 

 delicate outlines. After a careful examina- 

 tion of the evidence, Mr. Shaler has been 

 driven to suppose that at the close of the 

 glacial period the re-elevation of the land 

 must have been accomplished with a very 

 great suddenness. 



The Genesis of Inventions. In a paper 

 read before the Anthropological Society of 

 Washington, on "The Genesis of Inven- 

 tions," Mr. Franklin A. Seely proposes the 

 term Eunematics to designate the study of 

 invention. He lays down, as fundamental 

 postulates of this science, that, given any 

 artificial implement or product, we must 

 assume that there was a time when it did 

 not exist ; that before it existed there must 

 have been a creature capable of producing 

 it ; and that such creature before producing 

 it must have been conscious of needing it, 

 or must have had use for it. Further, that 

 every human invention has sprung from 

 some prior invention or from some prior 

 known expedient; that inventions always 

 generate wants, and these wants generate 

 other inventions ; that the invention of tools 

 and implements proceeds by specialization ; 

 and that no art makes progress alone. The 

 last four of these propositions are verifiable 

 from the history of any and of all modern 

 inventions ; the three former are deduced, 

 and must be confirmed, if they need con- 

 firming, by the study of prehistoric inven- 

 tions. In illustration of their force, Mr. 

 Seely produces a theoretical study of the 

 invention of the stone hatchet, a tool which 

 represents the earliest human workmanship 

 of which any knowledge has come to us, 

 and presents in its rudest form the evi- 

 dences of being the fruit of long-antecedent 

 growth. When men used wooden poles for 

 pikes, they found that their weapons were 

 better if they were pointed. One man found 

 that he could point pikes by rubbing them 

 back and forth on a certain gritty stone he 

 had. Other men brought their pikes to 

 him to be sharpened. Then they found 



that they could sharpen them themselves 

 on other stones. The sharp edge of a cliff 

 was found to be particularly good for this 

 purpose, and, when it was rubbed dull, an- 

 other cliff-edge was looked out. Then, by 

 some accident, the dulled cliff-edge was 

 broken off, and a new edge, possibly even 

 sharper than the old natural edge, was pre- 

 sented. The step was not long from this 

 discovery to designedly breaking off cliff- 

 edges. Then some one discovered that the 

 broken piece, fixed so as to be steady, or 

 held in the hands, would also cut. When 

 the stick-sharpener found that he could hold 

 the stick firmly and trim it by passing over 

 it the sharp stone held in the hand, he had 

 a flint knife. Another series of experi- 

 ments led to inserting the sharp stone into 

 a handle, and another series to the differ- 

 entiation of stones of different shapes and 

 sizes for various purposes. Parallel with 

 these processes were those of the develop- 

 ment of cords for tying, from the first acci- 

 dental shred of bark to fabricated strings 

 of twisted bark or cut strips of hide. 



Parental Peculiarities in Fishes and 

 Frogs. Fish and frogs arc not usually re- 

 garded as very careful parents, but a few 

 species exercise something like a particular 

 care for their young. Sticklebacks build 

 nests for the reception of the eggs, and the 

 males watch them and defend them against 

 intruders. The males of sea-horses {Hippo- 

 campi) and pipe-fishes are provided with 

 pouches in the under side of the body, re- 

 minding us of those of the opossum, in 

 which the eggs are put after having been 

 cast by the female, and are cared for till 

 they are developed. These pouches seem 

 also to be a kind of home for the young. 

 The female of the genus Solenostoma also 

 has a pouch, formed by the union of the 

 ventral fins with the body, in which the 

 ejrS are laid and hatched, and this is fur- 

 nished with a series of long, thread-like 

 bodies bearing small projections, for the 

 attachment of the eggs, and possibly for 

 the nutrition of the young. The skin and 

 tissues of the under-body of the mother As- 

 predo y when the egg-laying season comes 

 round, assumes a soft, spongy texture, to 

 which the eggs adhere till they are hatched, 

 when the skin becomes smooth again. The 



