October 14, 1897 J 



NATURE 



571 



The difference of temperature 'between stations in a valley 

 and upon a hill is one of considerable importance to agricul- 

 turists, and has occasionally engaged the attention of observers 

 both in this country and abroad. The Agricultural School at 

 Scandicci, near Florence, has made comparative observations 

 during the whole of the year 1895 ^'^ two stations, one being 

 situated in a plain, and the other about 220 feet higher, on the 

 side of a hill, both having a north aspect, and the thermometers 

 sheltered from rain and terrestrial radiation. The detailed ob- 

 servations and generalisations are published in the Bolkttino 

 Mensile of the Italian Meteorological Society for August last. 

 The results are very interesting, and show that in the plain the 

 minimum temperature is generally lower, while the maximum is 

 higher than that on the hill ; in other words, the plain is colder 

 during the night and warmer during the day. The mean 

 annual temperature in the plain was nearly 3° below that on 

 the hill. 



Euclid's eleventh axiom has furnished material for discussion 

 for many generations of mathematicians, and the latest contri- 

 bution we have received in this direction is a series of short 

 notes by Mr. Warren Holden, of Girard College, Philadelphia, 

 beginning with a reprint from the American Mathematical 

 Monthly, of an attempt to demonstrate the axiom, and including 

 two separate proofs of the thirty-second proposition not in- 

 volving the use of the term " parallel." Seeing that mathe- 

 maticians have so fully investigated the geometry of non- 

 Euclidian space, it need hardly be mentioned that Mr. Holden's 

 proofs are based on alternative assumptions. 



The Stone Age of Phenicia has been elucidated by Prof. G. 

 Zumoffen, and he has published his results in an illustrated 

 paper in F Anthropologie (viii., 1897, pp. 272, 426). Typical 

 palaeolithic implements have been found at seven stations. The 

 forms known under the names of Chellian and Mousterian 

 occur as well as other types. The Neolithic Age is characterised 

 in Phenica, as everywhere else, by the presence of polished 

 stone implements and coarse pottery. Four new stations have 

 been discovered, in addition to the two found by Mr. Chester 

 and described by Dawson in 1884. 



The decorative art of the Indians of the North Pacific Coast 

 is the subject of a very instructive and well-illustrated paper by 

 Dr. Franz Boas {Bull. Am. Mus. Nat. Hist. , New York, vol. ix. 

 p. 123). The subjects are almost exclusively animals; each 

 animal is characterised by certain symbols, and great latitude is 

 allowed in the treatment of all features other than symbols. 

 For example, the symbols of the beaver are large incisors, scaly 

 tail, and a stick held in the fore-paws ; of the hawk, a large 

 curved beak, the point of which is turned backward so that it 

 touches the face, &c. These symbols are often applied to 

 human faces. It appears that the artist first tried to characterise 

 the animals he intended to represent by emphasising their most 

 prominent characteristics ; these gradually became symbols, ] 

 which were recognised even when not attached to the animal 

 form. Dr. Boas very cleverly traces the distortions that result from 

 the endeavour of the artist to adjust the animal to the decorative 

 field in such a manner as to preserve as far as possible the 

 whole animal and bring out its symbols most clearly, but with- 

 out any idea of perspective. The representations are com- 

 binations of symbols of the various parts of the body of the 

 animal, arranged in such a way that if possible the whole animal 

 is brought into view. The arrangement, however, is so that the 

 natural relation of the parts is preserved, being changed only by 

 means of sections and distortions, but in such a manner that the 

 natural contiguity of the parts is preserved. The success of 

 the artist depends upon his cleverness in designing lines of dis- 

 section and methods of distortion. When he finds it impossible 

 to represent the whole animal he confines himself to rearranging 

 NO. 1459, VOL. 56] 



its most characteristic parts, always, of course, including its. 

 symbols. There is a tendency to exaggerate the size of the 

 symbols at the expense of other parts of the subject. 



Prof. Penck publishes in the Zeitschrift der Geselhchaft fiir 

 Erdkmtde zu Berlin an important contribution to the literature 

 of the geology of the North- west Highlands of Scotland, from the 

 standpoint of geomorphology. The author visited the region iiv 

 question after the International Geographical Congress in 1895, 

 and concentrated his attention chiefly on two points — the con- 

 ditions under which the Torridonian sandstones were laid down, 

 and the dynamical interpretation of the phenomena of the Bert 

 More and Moine thrust- planes. The breccias lying immediately 

 over the old gneiss are compared with formations observed by 

 Dr. J. Walther in the peninsula of Sinai, and Prof. Penck 

 suggests that the Torridon sandstones were laid down under 

 climatic conditions similar to those now found in the latter 

 region. From a minute discussion of the " experiments in 

 mountain-building" of Cadell, Willis, and others, it is concluded 

 that lateral thrust action only affects strata near the surface, but 

 that in a^typical case three different forms of displacement occur : 

 simple sliding near the surface, a complex movement of sliding, 

 and dislocation below that, and a movement resembling the 

 first in the lowest layers of all. These three stages in the forma- 

 tion of " fold "-mountain ranges are recognised as being at 

 present exposed in the North German Plain, the Alps and 

 Appalachian Mountains, particularly the Glarus Alps, and the 

 north-west of Sutherlandshire, respectively. 



The idea that the many varieties of igneous rock found in- 

 a single district may have originated by differentiation from a 

 single deep-seated rock-magma, is now familiar to geologists ;, 

 but a more novel idea is suggested by Prof. Cole in a recent paper 

 on ' ' Slieve Gallion " (Sci. Trans. Roy. Dublin Soc. , vol. vi. 

 part 9). He suggests that the fundamental earth-magmas may 

 really be of extremely simple composition, and that the mineral 

 complexity of plutonic rocks as we know them depends on the 

 number of times an original magma has been remelted in a new 

 environment, absorbing (or being absorbed) by substances of 

 different composition. He is led to this conclusion by the 

 phenomena of a granitic intrusion of Devonian age in the 

 " Dalradian " schists of Slieve Gallion. The intrusive rock 

 varies in composition from an aplite to a quartz-diorite, accord- 

 ing to the surrounding material which it has partly absorbed as 

 it intruded through it. 



The current number of the Centralblatt fiir Bakteriologiey 

 Part ii., contains a paper by Messrs. Russell and Weinzirl orb 

 the rise and fall of bacteria in cheddar cheese. Determinations 

 of the number of bacteria per gram in American cheddar cheese 

 were made at different stages of the ripening process, whilst the 

 varieties present were roughly classified under the heads of 

 lactic acid bacteria, gas-producing bacteria, casein-digesting 

 bacteria, and inert bacteria or those having apimrently no effect 

 on casein in milk cultures. In samples of green cheese examined 

 immediately after it was removed from the press, a diminution, 

 in the numbers of bacteria present was noted as compared with 

 the initial number present in the milk. This period of bacterial, 

 decline, however, generally lasts but two days, and is followed 

 by a very marked increase in the numbers present later on, so 

 much so that in the course of a few days, generally from eight 

 to twenty, the germ contents may increase many-fold. This active 

 bacterial growth is not by any means equally distributed amongst 

 all the varieties of microbes present, but is almost exclusively 

 confined to the lactic acid group of organisms, the gas-producing 

 bacteria as well as the casein-dissolving varieties rapidly dis- 

 appearing. The relation between this pronounced multiplication 

 of the lactic acid bacteria and the ripening process in cheese is 

 not yet exactly established, although the presumption is that 



