Fib, 27, 1879] 



NATURE 



397 



On2 of the most interesting questions in American archaeology 

 has long been that of the age of the " mound -builders." Modem 

 views seem now opposed to a prehistoric date for these people. 

 Amongst other American workers who have inclined to the more 

 recent date of these structures may be mentioned S, F. Haven, 

 who considered the ancestors of the present Indians to have 

 been the authors of these erections, and Dr. P. J. Famsworth, 

 who believed that the mound-builders were identical in race 

 with the historical Indians of North America. On this subject 

 a paper read before the Congres International des Americanistes, 

 1877, by M. F. Force, has just been reprinted in pamphlet form 

 by Clarke and Co., Cincinnati, 1879, entitled " To what Race 

 did the Mound -builders belong?" The following are some of 

 the author's conclusion-; : — That so far as indications are given 

 by the growth of vegetation, it is not necessary to hold that any 

 of the works were abandoned more than one thousand years 

 ago. That the absence of all tradition concerning the mounds 

 among the recent Indians is no proof of their great antiquity, 

 as Indian tradition is short-lived and evanescent. Although the 

 advent of De Soto with his armed followers, pillaging and 

 ravaging the country, must have been calculated to make a deep 

 impression, yet, when Europeans visited the country a century 

 and a half later, they found not a vestige of a tradition of De 

 Soto. Finally, Mr. Force considers that the mound-builders 

 were tribes of Indians, more advanced than 'the Algonquins or 

 the Dakotahs, but much less advanced than the Aztecs or the 

 Peruvians, and on the same plane with the Pueblo Indians, and 

 that they were living in full prosperity in the time of Charle- 

 ma^e. Mr. Force reviews the evidence as to their antiquity 

 derived from an examination of crania from these mounds, and 

 endeavours to prove that either the skulls^were not obtained 

 from the mounds under consideration, or in other instances 

 would not bear the conclusions based on their examination. 



A CURIOUS thermo-magnetic motor, devoid, probably, of prac- 

 tical value, but having some scientific interest, has been devised 

 by Prof. Houston and Thomson {Journal of the Franklin Insti- 

 tute). A disk or ring of thin steel is mounted on a vertical axis 

 so as to be quite free to move with its edges opposite the poles 

 of a horse-shoe magnet. The wheel of course becomes magne- 

 ti; ed by induction. On heating a section of it, It begins to move. 

 The reason is, that the heated section has its coercitive force 

 increased, and so, being less powerfully m^^etised by the 

 induction of the adjacent pole, than the part next it, the attrac- 

 tion exerted by the pole on this latter part is sufficient to cause 

 motion. A constant source of heat gives continuous rotation. 

 The disk must be sufficiently thin to prevent its acquiring a 

 uniform temperature. The heat may be applied at diametrically 

 opposite parts, with similar effi;ct. What renders the motor of 

 little value is the amount of heat required being so enormous as 

 compared with the force developed. 



The Monats Berichte der Berliner Akademie (September and 

 October 1878) contain some researches by M. Panlzow on the 

 spectrum of oxygen : as, however, M. Paalzow has fallen into 

 the old and common mistake of taking the spectnun of carbonic 

 oxide for the spectrum of oxygen, he cannot be said to have 

 made any decisive addition to our knowledge. 



A Ceylon paper furnishes some interesting notes respecting 

 the cultiu-e of the cinchona tree in the island. The variety 

 known as C. succirubra yields a large quantity of bark, and is 

 so hardy that, though the proper zone of elevation for its culture 

 is from 2,000 to 4,500 feet, many planters are induced to try it at 

 higher elevations. The zone for C. officinalis is from 4,000 feet 

 upwards, and it has been grown on Dodabetta at a height of 

 8,000 feet, but in that ca>e the bark of the unmoi-sed tree 

 becomes covered with lichens. C. calisaga will grow wherever 

 the last-named variety does. Cinchona officinalis is highly 



recommended as a sheltering tree for coffee-shrubs against the 

 effects of wind. 



The first number of the Journal of the Russian Physical and 

 Chemical Society (both societies now united) contains an inter- 

 esting paper by M. Beketoff on the specific heat of hydrogen 

 when compounded with palladium ; a paper by M. Ponomareff 

 on derivatives from uric acid ; additions and corrections, by 

 Prof. Menschutkin, to his papers on etherisation of secondary 

 alcohols ; two papers on organic chemistry by MM. Kiabinine, 

 Saytzeff, and Semlianitzin ; and a paper by M. Lerroantoff on 

 the chemical and photographic action of light. Many very 

 interesting notes give a very complete account of recent work in 

 chemistry. 



The formation of hail and the various causes which contribute 

 to it are still a very obscure question in meteorology. The fc'- 

 lowing points on which information is desired have lately been 

 indicated by M. Colladon : — i. Dates as exact as possible, and 

 made comparable with the hour at Paris, Berne, or Geneva, of 

 the commencement and end of th^ hail shower ; extent of the 

 surface covered. 2. Average and maximum dimeasions of hail- 

 stones, their form, the average or maximum number of layers 

 they present. Do the successive layers increase in thickness 

 from the central nucleus ? 3. Apparent form and elevation of 

 hail clouds ; have they tlie appearance of a vast continuous 

 gyratory movement, or simply of movements of attraction and 

 repulsion ? Multiplicity of flashes, their average number per 

 minute ; are they, or not, accompanied by resounding noises and 

 frequent descents of lightning on the ground ? or are they mostly 

 mute? Are there notable falls of hail without apparent and 

 well-marked electrical phenomena ? 4. Average temperature of 

 the air before or during an electric storm, and temperature of the 

 rain-water accompanying it, at the moment of its fall. M. 

 Colladon has contrived an inexpensive apparatus for measuring 

 the last item {La Nature, February 15). A funnel conducts the 

 rain to a capsule holding the bulb of a minimum thermometer 

 which has the upper part of its stem bent horizontally and a scale 

 attached to this part. 



In a note on brewing contained in a report on Sapporo and 

 Ishcari (Japan) we read that the beer is poor, weak stuff that will 

 not keep. In course of time, 'however, it is fully expected that the 

 art of brewing will succeed, more especially as a native director 

 has spent several years in America and Europe devoting his 

 attention to brewing. The hops used, it seems, are imported, 

 and foreign hop seed has been sown, the plants raised from 

 which appear to be doing well. The wild hrps, which are fomid 

 in great abundance on the road from Morarau to Sapporo, and 

 have been found to be unsuitable for brewing in their wild ; tate, 

 are now being cultivated, as it is supposed that by care and 

 attention they will prove to be as good if not better than foreign 

 hops. Consequently great pains are now being taken with these 

 hop plantations. 



The additions to the Zoological Society's Gardens during the 

 past w eek include a Green Monkey {CercopUhecus callitrichus) 

 firom West Africa, presented by Mr. Douglas Murray ; a Bennett's 

 Wallaby {^Halmaturus benmttii) from Tasmania, presented by 

 Mr. W, E. Windus ; a Common Hare {Lepus mropceus), British 

 Isles, presented by Mr. Alfred Withers ; two Indian Barred 

 Doves {Geopdia striata), a Chinese Tiu-tledove {Turtur cAinensis) 

 from India, presented by Capt. H. Braddick ; a Tayra {Galictis 

 barbara) from Panama, two Grand Galagcs (Galago crassicau- 

 datus) from East Africa, three Australian Wild Ducks {Anas 

 superciliosa) from Australia, two Cardinal Grosbeaks {Cardituiiis 

 virginianus) from North America, purchased ; a Spotted Eagle 

 Owl {Bubo niaculosus) from Africa, deposited ; two Prairie 

 Marmr ts {Cynomys ludovicianus') from North America, received 

 in exchange. 



