250 



THE POPULAR SCIENCE MONTHLY. 



be carried to a distance by a few horizontal 

 flues of large dimensions, terminating in 

 lofty chimneys on a hillside or distant plain, 

 as is done at the mercury-mines of Idria 

 and some other places. With a little care 

 in the arrangements, the smoke would be 

 wholly deposited in the horizontal flues, 

 and would be available for agricultural uses. 



The Tomato - Plant as a Protection 

 against Insects. In a peach-orchard plant- 

 ed by M. Siroy, a member of the Valparaiso 

 Society of Horticulture, the trees at first 

 grew well and strongly. But, on commen- 

 cing to bud, they were invaded by the cur- 

 culio ; and this insect was followed, as fre- 

 quently happens, by ants. While the trees 

 were thus infested, the idea occurred to M. 

 Siroy that by placing leaves around the 

 trunks and branches he might ward off the 

 rays of the sun, which were very powerful. 

 For this purpose he happened to choose 

 tomato-leaves. On the following day he 

 found the trees entirely free from their ene- 

 mies, not one remaining, except here and 

 there where a curled leaf prevented the to- 

 mato from exercising its influence. These 

 leaves he carefully unrolled, placing upon 

 them fresh ones from the tomato-vine, with 

 the result of banishing the last insect, and 

 enabling the trees to grow with luxuriance. 

 Wishing to carry the experiment still fur- 

 ther, he steeped in water some fresh leaves 

 of the tomato, and sprinkled with this in- 

 fusion other plants, roses and oranges. In 

 two days these were also free from the in- 

 numerable insects which covered them. 



The Age of Paleolithic Man. Dr. R. H. 

 Tiddeman contributes to Nature for Octo- 

 ber 5th a paper in which he reaffirms the 

 inter-glacial age of paleolithic man and of 

 the fauna with which he is associated. The 

 position not only of human but of animal 

 remains points clearly to the fact of their 

 existence subsequent to a deposit of glacial 

 drift, but previous to another deposit of 

 similar material. The facts may be taken 

 as part of the evidence which proves the 

 disappearance of a great ice-sheet which 

 covered Scotland, England, and portions of 

 the Continent, and the return of it after a 

 period of temperate climate during which 

 man and animals inhabited the region. 



The direct evidences of the inter-glacial 

 age of paleolithic man from the actual iu- 

 fraposition of his bones or implements are 

 stated as follows : 



1. Victoria Cave, Settle : a human 

 fibula under glacial till, and associated with 

 bones of Eltphas antiquus, Rhinoceros lep- 

 torhinus, hyena, hippopotamus, etc. 



2. At Wetzikon, Canton Zurich, a piece 

 of lignite containing basket-work lying be- 

 neath glacial deposits, and associated with 

 Elcphas antiquus and Rhinoceros lepiorhi- 

 nus. 



3. Near Brandon, Suffolk, implements 

 with bones not yet determined in brick- 

 earth beneath the great chalky bowlder- 

 clay of East Anglia. 



Dr. Tiddeman says the " Settle till is 

 undoubtedly of the age of the ice-sheet. 

 The Wetzikon lignite lies upon a glacial till 

 beneath a river-gravel on which are great 

 erratic blocks clearly indicating the pres- 

 ence of a great glacier posterior in date to 

 the organic remains. The Brandon imple- 

 ments are beneath the chalky bowlder- 

 clay." 



Inequality of the Oeean-Bed. In opening 

 the Geographical Section of the British As- 

 sociation at Glasgow, CaptainEvans said that 

 it was learned for the first time by the Chal- 

 lenger's results ably supplemented as they 

 had recently been by the action of the 

 United States Government in the Pacific, 

 and by an admirable series of soundings 

 made in the exploratory German ship-of-war 

 Gazelle that the unbroken range of ocean 

 in the southern hemisphere was much shal- 

 lower than the northern seas ; that it had 

 no features approaching in character those 

 grand abysmal depths of 2*7,000 and 23,500 

 feet found respectively in the North Pacific 

 and North Atlantic Oceans, as the greatest 

 reliable depths recorded did not exceed 17,- 

 000 feet. The general surface of the sea- 

 bed presented in general to the eye, when 

 graphically rendered on charts by contour 

 lines of equal soundings, extensive plateaux 

 varied with the gentlest of undulations. 

 There was one great feature common to all 

 oceans, and which may have some signifi- 

 cance in the consideration of ocean circula- 

 tion, and as affecting the genesis and trans- 

 lation of the great tidal wave and other tidal 



