70 



NATURE 



[September 19, 1912 



highest maximum had been recorded, a surprisingly 

 sudden decrease in intensity was indicated by the 

 actinometer; no cause for the change was discernible 

 in the deep blue of a perfectly clear sky, and observa- 

 tions were repeated as rapidly as possible until 

 10.45 Si-m., when the intensity had become very weak 

 and filmy clouds could be seen in the zenith in an 

 incipient stage of formation; by 11.30 the whole sky 

 was overcast with an alto-stratus formation. During 

 this time no change was registered in the brisk, 

 warm, northerly wind which had been blowing since 

 early morning, and the pressure, though slightly 

 below normal, showed the normal variation for this 

 time of day; so it seemed that the ultra-violet rays 

 had at last displayed their powers in an unquestion- 

 able manner. But after the upward turn in the 

 diurnal pressure curve set in, about 2 p.m., the 

 barometer rose at an unusual rate, and by sunset a 

 strong, cold, southerly wind was blowing, thus show- 

 ing that the transformations in the upper air of the 

 forenoon were due to the advance portion of a pressure 

 wedge overflowing the warm and relatively moist 

 surface current. It may be added here that no rain 

 fell anywhere near the place of observation for several 

 weeks after this display (although March is still well 

 within the rainy season of this region), nor have I, 

 up to the present time, heard of such general and 

 heavy rains over the earth during the latter part of 

 the month as would commensurate with such unusual 

 activity in the ultra-violet field of the sun. 



Dr. Ramsauer may claim that the mere fact of 

 condensation is sufficient proof of his theory, and this 

 brings up another matter referred to in his first letter 

 which I shall discuss briefly. He says : — " If we 

 neglect the purely local formation of nuclei in large 

 centres of industry, the ultra-violet . . . radiation of 

 the sun is chiefly responsible," &c., implying that con- 

 densation can take place only on an iiifinitely small 

 number of the solid impurities sustained in the air. 

 There are probably not so many factory chimneys 

 on the whole continent of South America as there are 

 in London, yet within the past few days an area of 

 several hundred thousand square miles in the central 

 section of this continent was covered by a shallow- 

 fog caused by dust particles, raised by the high winds 

 of a "dry cyclone," cooling by radiation into the 

 calm air of a rapidly following high-pressure area. 

 This is only a single instance of a phenomenon which 

 is very common indeed during the fall and winter in 

 all regions of the temperate zones, and it goes to 

 show that clean dust particles raised by the winds 

 from virgin soils are quite as effective as condensation 

 nuclei as the particles of waste products which escape 

 through the chimneys of manufacturing towns. If 

 dust particles can act so efficiently as nuclei in the 

 low-lying strata, why should they be denied this 

 agency when they appear in the higher regions of the 

 atmosphere? For their existence in those regions, 

 even far out into interplanetary space, is impressively 

 evidenced by the brilliancy of the twilight glow, the 

 meteor tracks, and the zodiacal light. 



L. G. SCHULTZ. 



Oficina Meteorol6gica Argentina, Observatorio 

 Magn(?tico, Pilar, C6rdoba, July 26. 



Antiquity of Neolithic Man. 



Recent excavations in St. Holier, Jersey, have 

 brought to light the following evidence bearing on the 

 antiquity of Neolithic man : — 



The soil beneath the town of St. Helier is, in 

 descending order, composed as follows : — 



(i) .\ deposit of blown sand and recent alluvium 

 from 4 ft. to 6 ft. thick. 



NO. 2238, VOL. 90] 



(2) A bed of brown sandy and clayey peat (with 

 relics of Gallo-Roman times). 



(3) A marine deposit, consisting of clay, shingle, 

 and shell-gravel, from 2 ft. to 5 ft. thick. 



(4) A bed of firm black peat and forest remains 

 which ranges from 5 ft. to 14 ft. in thickness. 



This peat and forest bed is traceable to the shore, 

 where it forms the well-known " submerged forest," 

 thence (as revealed by the dredge) across the channel 

 that separates the island from the continent, and 

 along the continental coast from Cape La Hague to 

 Finistcrre. 



This no doubt is all one with the post-glacial sub- 

 merged forests of the British Isles and north-western 

 Europe in general, for all through the flora and fauna 

 are the same, viz. oak, alder, birch, hazel, Juncus, and 

 Equisetum, with hazel nuts in profusion. Bos longi- 

 frons, red deer, and wolf, even elytra of the little 

 purplish-green beetle, Geotropus vernalis, are present 

 in this layer beneath St. Helier, as they are from 

 extreme north to south throughout the vast forest 

 area. 



This deposit, then, marks the period of the com- 

 mencement of land elevation which followed the sub- 

 sidence of glacial times, for it lies immediately upon 

 unmistakable rubble-drift and blue marine clay. 



Neolithic relics, in the way of stone implements and 

 fiagments of pottery, are very plentiful on the surface, 

 and in the upper levels, of this forest bed, but, so far 

 as I can ascertain, have never been recorded from the 

 strata beneath. 



In a series of excavations now in progress for the 

 foundations of a building in St. Helier, the strata as 

 above described have been cut through, and in the 

 blue clay beneath the forest bed (which here is 8 ft. 

 thick) were found Neolithic implements as follows : — 

 (i) A squared block of diorite about 6 in. in width 

 and in breadth, and about 2 in. thick, which has been 

 used as an anvil, apparently for chipping flints. It 

 is deeply scored on both sides. (2) A flat sandstone 

 pebble about j in. in diameter, which has been used 

 in the same way. (3) A flat pebble of dolorite about 

 a foot in length, 4 in. vt-ide at one end, and running 

 to a point at the other. 



This pebble has served three purposes, for it is 

 worn and abraded on the broad and fairly sharp end, 

 showing that it has been used as an axe ; again, on 

 the sharpest lateral edge, indicating use as an ordinary 

 meat-chopper ; finally, it is scored with many cuts on 

 the flat surfaces, having apparently been used as an 

 anvil for chipping flints. (4) Two good specimens of 

 the very typical fiat pebble implements of elongated 

 triangular form, bevelled at the broad end — a crude 

 form of implement which has persisted until the dol- 

 men period, and occurs plentifully amongst the latest 

 Neolithic relics. 



Besides these there were numerous flint chippings, 

 cores from which flakes had been struck, and some 

 crude flint implements with no characteristic detail. 



In the same stratum as these, and in a layer of 

 yellow day which lies beneath, flint implements of 

 decided Chellian, .\cheulian, and Mousterian types 

 are frequent, but the relics above specified are very 

 clearly and decidedly Neolithic. 



.\s the portion of the forest bed at this spot must 

 represent the vegetation that first fringed the land as 

 it recovered 7rom the depression of glacial times, and 

 these relics lie beneath it, we cannot but conclude 

 that the Neolithic races date from a period far more 

 remote than has usually been assigned to them, and 

 that they must, in fact," date back nearly into the last 

 glacial period. 



Question may arise as to the possibility of a dis- 

 turbance of the' area by floods or other agencies, and 



