130 



SCIENCE. 



[N. S. Vol. II. No. 31. 



heat flowed easilj-, being carried ofi' by a 

 quantity of cold water resting on it, the 

 water being continually renewed so as to 

 maintain at this end nearly a constant low 

 temperature. The difference of tempera- 

 ture between the two faces was about 200° 

 C. The most successful experiments were 

 made on slate and granite. Each experi- 

 ment lasted about two hours, and after the 

 first hour the temperature of the three 

 thermo-electricjunctions remaiued sensibly 

 constant. 



The results showed in both cases that the 

 conductivity at the higher temperature was 

 less than at the lower. The differences 

 were very decided and such as must cer- 

 tainly be taken into account in all discus- 

 sions of the transmission of heat by conduc- 

 tion in hot bodies. The work is very im- 

 portant and should be, as it doubtless will 

 be, extended to greater variety of material 

 and wider range of temperature. 



T. C. M. 



SCIENTIFIC NOTES AND NEWS. 

 PITHECANTHEOPUS EEECTUS. 



Me. Aethue Keith contributes to the 

 July number of Science Progress a careful 

 account of human fossil remains ; he sum- 

 marizes his conclusions as follows : 



" Our human geological record stretches as 

 yet back only to an early post-tertiary pe- 

 riod. ^ The millions of men that must have 

 lived in these early times are known to us 

 by only four specimens complete enough to 

 permit ■ of their reconstruction. But, tak- 

 ing these as samples of their race, we can 

 say with some assurance that man has not 

 changed much since the Tertiary period of 

 the earth's history closed. The majority 

 of men were distinctly and considerably 

 smaller-brained than the great majority of 

 the men that now people the earth's sur- 

 face. Their faces, jaws, teeth and muscular 

 ridges were more pronounced. Since Ter- 

 tiai-y times the human structural progress 



has lain in an increase of brain and a 

 diminution in the masticatory and ahmen- 

 tary systems. In these features we maj^ 

 suppose that early Quaternary man ap- 

 proached the primate ancestors of the race ; 

 in these features he certainly comes nearer 

 the present simian type. But, for the pur- 

 pose of giving us a clue to the human line 

 of descent, the fossil remains at present 

 known assist us not one single jot. Their 

 configuration is quite conformable to the 

 theory of a common descent ; they bear 

 out the truth of that theory. They also 

 show us that man since the Tertiary period 

 has changed structurally very little. There 

 is nothing remarkable in this, for allied 

 primitive forms (Paleopitheeus sivalenses^ and 

 DryopUhecus^ ) demonstrate to us that, since 

 the Miocene period, the anthropoid type has 

 changed but slightly. We need not then 

 be surprised at being obliged to seek deep 

 within the Tertiary formations the eviden- 

 ces of human descent." 



A PEOPOSED COUNTY PAEK SYSTEM. 



At a recent meeting of the Natural Sci- 

 ence Association of Staten Island, Mr. Wal- 

 ter C Kerr, President of the Association, 

 read a paper on 'A proposed County Park 

 System.' Mr. Kerr urged the desu-ability 

 of putting into execution, before it is too 

 late, some plan to preserve what still re- 

 mains of the dense forests which covered 

 the island in earlier times. He does not 

 consider it feasible to establish at once a 

 series of parks ^dth the attendant expenses 

 of immediate improvements, but simply 

 " the purchase by the county, at reasonable 

 prices, of various tracts to be held as public 

 land, and eventually, when the county be- 

 comes more densely populated, to become a 

 park system joined by county roads. The 

 larger and more distant tracts, however, 

 woiild possess, as the years go by, an inter- 

 est far greater than any conventional park 

 could yield, for with the extensive flora of 



