1 1: 



NATURE 



[November 29, 1S94 



north-west of Ireland, the west of Scotland, and Norway. The 

 greater part of the paper is occupied by an account of the 

 distribution of the varieties of fjord-coasts in different 

 parts of the world, and the generalisation is made that 

 there are none of those coast- features outside the limits 

 of lands which bear signs of recent glaciation. Herr 

 Dinse has made a complete discussion of the principal 

 dimensions and the exact configuration of eighty-three fjords in 

 all pans of the world, taking his data from the largest-scale 

 sea-charts available for each region, and these figures are 

 printed as an appendix. The paper is illustrated by a few 

 contoured maps of fjords, and by profiles showing their longi- 

 tudinal and transverse sections. 



The Gradient-Telemeter Level, of which we give an illus- 

 tration, should be of service to civil engineers and surveyors. 

 Its novelty consists in the absence of a vertical circle, while a 

 circle tilted out of the horizontal plane takes the place of the 

 horizontal circle in an ordinary theodolite. So constructed, the 

 instrument can be used to obtain linear distances, gradients, and 

 differences in level of objects without the use of land-chain or 

 tape. The circle is divided into natural tangents instead of 

 degrees. When the reading is zero, the telescope is horizontal, 

 but by rotating the circle, the telescope is • inclined to the 

 horizontal line, and the inclination is indicated by the pointer 

 to the circle. .\s an examp'e of the use of the instrument, 



suppose the whole of the levelling staff to be below the hori- 

 zontal line of sight. Setting the circle for a gradient of one in 

 twenty-five, let the rcadirg of the staff be 13S6. Now set the 

 circle so that the index points to a gradient of one in twenty, 

 and let the reading be 8'45. The difference between these two 

 readings is 5'4I, and, eliminating the decimal point, the number 

 obtained — 541 — is the horizontal distance in feet between the 

 instrument and the staff, without any further calculation. Other 

 pain of gradients may be used, and the difference of their staff- 

 readings gives the linear horizontal distance. The instrument 

 thus greatly aimplifies many surveying operations. 



A COLLECTION of valuable notes on the aborigines of various 

 parts of Australia is given in the November Journal o[ the 

 Anthropological Institute. The notes, which take the form of 

 answers to questions on the manners, custom^, religions, super- 

 stitions, &c.,of the native tribes of Australia, have been col- 

 lected by iJr. E. C. Stirling. The natives arc divided into 

 NO. 1309. VOL. 5 l] 



innumerable tribes, and different customs prevail every two 

 hundred miles or so. Arithmetic is beyond their comprehension. 

 Most of the tribes appear to h.ive distinctive names for one and 

 two, but for three they say two and one ; for four, they say two 

 and two ; and for five, two two and one. The fingers are 

 used in counting, but numbers beyond five are very seldom 

 used. Numbers greater than len are usually described as 

 " plenty " and " many," and explained by opening and closing 

 the hands several times. The tribes have a very limited know- 

 ledge of the measurement of time. They tell the time of day 

 by the sun, and speak of the diiTerent limes of the position of 

 the sun. They reckon by so many moons, and determine the 

 year by the seasons ; but they have no knowledge of the con- 

 stellations, nor have they any names for the months, or moons, 

 as they call them, or any recognised beginning of the year, nor 

 artificial timekeeper of the nature of sun-dials, though the lengths 

 of the shadows of trees is used by some tribes to determine the 

 time of day. The heavenly bodies are not worshipped, neither 

 are any ceremonies performed at the new moon, sunrise, sunset, 

 the solstices, equinoxes, S;c. The Milky Way is supposed to 

 be the largest creek or river. A fresh sun is believed to shine 

 every day, and the phases of the moon are explained by the 

 prevailing course of the wind and prevailing quarter of the rain. 

 Eclipses, rain, thunder, lightning, rainbows, wind, and Aurora 

 Australis are supposed to be the work of evil spirits. Many 

 other beliefs are described in the notes, which will be read with 

 great interest by every student of anthropology and folk-lore. 



The mutual alterations effected between an invading igneous 

 m.iss and the rock which it invades, have long been the subject 

 of much study and speculation. -•Vn interesting case, present- 

 ing some exceptional features, has recently been described by 

 Prof. Cole (Trans. Roy. Dublin Soc. vol. v. (n.s.) No. 5). 

 On the coast of Co. Down, the Ordovician strata are cut by 

 numerous basic dykes. In some cases, material of more acid 

 composition has intruded at a later da'e, and, forcing its way 

 along the same lines of weakness as the earlier basic material, 

 has produced " compound " dykes. It is one such compound 

 dyke, at Glasdrumman, consisting of basaltic andesitc rifted 

 lengthwise by later eurite, that Prof. Cole describes in detail. 

 The new-comer has rc-melled the more easily fusible andesite, 

 and the two magmas have mixed along the contact. Various 

 stages of mixture are described, but the most interesting facts 

 are those concerning the large crystals of quartz and felspar 

 which abound in the marginal portions of the eurite. These 

 crystals have evidently consolidated under other, and earlier, 

 conditions than the main mass of the rock, since portions of 

 the curite-matrix have eaten their way into them before solidi- 

 fying. But crystals undoubtedly so corroded are also found in 

 the andesite, into which they must have floated from the eurite. 

 The presence in a rock of crystals of evident foreign origin is 

 no new thing, but hitherto it has, in all such cases, been either 

 shown or assumed that they were caught up by the rock in 

 which they are found from some other into which it had 

 intruded ; whereas, here, it is the invading eurite that has 

 parted with its crystals for the benefit of its host. Thus the 

 common dictum, that "an enclosed block must be older than 

 the rock immediately enclosing il," is apparently controverted ; 

 yet, since consolidation is the datum from which age is 

 measured, it becomes a decidedly nice point in geological 

 nomenclature whether a partially re-fused rock can be allowed 

 to pass as entirely older than the rock which has re-melted it. 



Some interesting particulars concerning " aventurine glass," 

 one of the most curious products of the world-renowned glass- 

 works at .Murano, near Venice, are given in the current number 

 of the --/«;(■»■;■> u« /ournal cj Hcicn.t, by Mr. Henry S. Washing- 

 ton. Its name is derived from its supposed discovery " by 



