148 



SCIENCE. 



[Vol. XVII. No. 423 



onust continue to exist forever, if in a perfect fluid free from all 

 friction they are once generated, as a result of impacting motion. 



There is something very attractive in the simplicity of this the- 

 ory of the constitution of matter which has been advocated by 

 Sir William Thomson. He illustrates it by likening the form of 

 atoms to smoke-rings in the atmosphere, which, were they only 

 formed under circumstances such as above described, must con- 

 tinue to move without changing form, distinguished only from 

 the surrounding medium by their motion. As long as the original 

 conditions of the liquid exist, they must continue to revolve. 

 Nothing can separate, divide, or destroy them; and no new units 

 can be formed in the liquid without a fresh application of creative 

 impact. 



The doctrine of the conservation of energy is a second power- 

 ful instrument of research that has developed within our own 

 times. How it has cleai-ed away all the old cobwebs that formerly 

 incrusted our ideas about the simplest agencies that are at work 

 around us ! How it has so simplified the teaching of the laws 

 that order the conversion of internal motions of bodies into phases 

 which represent light, heat, electricity, is abundantly proved by 

 the facility with which the mechanicians are every day snatching 

 the protean forms of energy for the service of man with increaa^ 

 ing economy. These great strides which have been made in 

 physical science have not as yet incited much original work in 

 this colony. But, now that physical laboratories are established 

 in some degree at the various college centres, we will be expected, 

 ere long, to contribute our mite to the vast store. 



In practical works of physical research we miss in New Zealand 

 the stimulus the sister colonies receive from their first-class ob- 

 servatories, supplied with all the most modern instruments of 

 research, wielded by such distinguished astronomers as Ellery, 

 Russell, and Todd, whose discoveries secure renown for thei'r sep- 

 arate colonies. I am quite prepared to admit that the reduplica- 

 tion of observatories in about the same latitude, merely for the 

 study of the heavenly bodies, would be rather a matter of scientific 

 luxury. The few degrees of additional elevation of the south 

 polar region which would be gained by an observatory situated 

 «ven in the extreme south of New Zealand could hardly be ex- 

 pected to disclose phenomena that would escape the vigilance of 

 the Melbourne Observatory. But star-gazing is only one branch 

 of the routine work of an observatory. It is true that we have 

 a moderate but efficient observatory establishment in New 

 Zealand, sufiicient for distributing correct mean time, and that 

 our meridian distance from Greenwich has been satisfactorily 

 determined by telegraph ; also, thanks to the energy and skill of 

 the Survey Department, despite most formidable natural obstruc- 

 tions, the major triangulation and meridian circuits have estab- 

 lished the basis of our land-survey maps on a satisfactory footing, 

 60 that subdivisions of the land for settlement, and the adoption 

 and blending of the excellent work done by the provincial gov- 

 ernments of the colony, are being rapidly overtaken. Further, I 

 have already recalled how much the colony is indebted to the 

 •mother country for the completeness and detail of the coastal and 

 harbor charts, but there is much work that should be controlled 

 by a physical observatory that is really urgently required. I may 

 give a few illustrations. The tidal movements round the coast 

 are still imperfectly ascertained, and the causes of their irregular 

 variations can never be understood until %ve have a synchronous 

 system of tide-meters, and a more widely extended series of deep- 

 sea soundings. Excepting the ' ' Challenger " soundings on the 

 line of the Sydney cable, and a few casts taken by the United 

 States ship "Enterprise,"' the depths of the ocean surrounding 

 New Zealand has not been ascertained with that accuracy which 

 many interesting problems in physical geography and geology 

 demand. It is supposed to be the culmination of a great subma- 

 rine plateau; but how far that plateau extends, connecting the 

 southern islands towards the great Antarctic land, and how far 

 to the eastward, is still an unsolved question. Then, again, the 

 direction and intensity of the magnetic currents in and around 

 New Zealand require further close investigation, which can only 

 be controlled from an observatory. 



Even in the matter of secular changes in the variation of the 

 compass we find that the marine charts instruct that an allowance 



of increased easterly variation of two minutes per annum must be 

 made, and, as this has now accumulated since 1850, it involves a 

 very sensible correction to be adopted by a shipmaster in making 

 the land or standing along the coast ; but we find from the re- 

 cently published work of the '• Challenger" that this tendency to 

 change has for some time back ceased to affect the New Zealand 

 area, and as the deduction appears only to have been founded on 

 a single triplet observation of the dip taken at Wellington, and 

 one azimuth observation taken off Cape Palliser, it would be well 

 to have this fact verified. With regard to the local variation in 

 the magnetic currents on land and close in shore, the requirement 

 for exact survey is even more imperative. Capt. Creak, in his 

 splendid essay, quotes the observations made by the late surveyor- 

 general, Mr. J. T. Thomson, at the Bluff Hill, which indicate that 

 a compass on the north side was deflected more than 9*^ to the 

 west, while on the east side of the hill the deflection is 46° to the 

 east of the average deviation in Foveaux Strait. He adds that if 

 a similar island-like hill happened to occur on the coast, but sub- 

 merged beneath the sea to a sufficient depth for navigation, 

 serious accidents might take olace ; and he instances a case near 

 Cossack, on the north coast of Australia, when H. M. Medea, sail- 

 ing on a straight course in eight fathoms of water, experienced a 

 compass deflection of 30° for the distance of a mOe. 



A glance at the variation entered on the meridian circuit maps 

 of New Zealand shows that on land we have extraordinary differ- 

 ences between different trigonometrical stations at short distances 

 apart. For instance: in our close vicinity, at Mount Pleasant, 

 behind Godley Head lighthouse, at the entrance to Lyttelton har- 

 bor, tbe variation is only 9" 3' east, or fi" less than the normal; 

 while at RoUeston it is 15° 33', and at Lake Coleridge 14° 3'. In 

 Otago we have still greater differences recorded, for we find on 

 Flagstaflf Hill, which is an igneous formation, 14° 84', while at 

 Nenthorn, thirty miles to the north, in a schist formation, we find 

 an entry of 85° 41'. 



In view of the fact that attention has been recently directed, to 

 the marked effects on the direction and intensity of the terrestrial 

 magnetic currents of great lines of fault along which movements 

 have taken place, such as those which bring widely different geo- 

 logical formations into discordant contact, with the probable pro- 

 duction of mineral veins, this subject of special magnetic surveys 

 is deserving of being undertaken in New Zealand. In Japan and 

 in the United States of America the results have already proved 

 highly suggestive. A comparison between this country and Japan 

 by such observations, especially if combined with systematic and 

 synchronous records by modern seismographic instruments, would 

 be of great service to the physical geologist. 



There are many features in common, and many quite reversed, 

 in the orographic and other physical features of these two coun- 

 tries. Both are formed by the^ crests of great earth-waves lying 

 north-east and south-svest, and parallel to, but distant from, con- 

 tinental areas ; and both are traversed by great longitudinal faults 

 and fissures, and each by one great transverse fault. Dr. Nauman, 

 in a recent paper, alludes to this in Japan as the Fossa 3Iagna; 

 and it corresponds in position in relation to Japan with Cook Strait 

 in relation to New Zealand. But the Fossa Magna of Japan has 

 been filled up with volcanic products, and is the seat of the loftiest 

 active volcano in Japan. In Cook Strait and its vicinity, as you 

 are aware, there are no volcanic rocks ; but there and southward, 

 through the Kaikouras, evidence of fault movements on a larger 

 scale is apparent. It would be most interesting to ascertain if the 

 remarkable deviation from the normal, in direction and force of 

 the magnetic currents, which are experienced in Japan, are also 

 found in New Zealand : for it is evident, that, if they are in any 

 way related to the strain of cross fractures in the earth's crust, 

 the observation would tend to eliminate the local influence of the 

 volcanic rooks which are present in one case and absent in the 

 other. 



With reference to earthquakes also, few, if any, but very local 

 shocks experienced in New Zealand have originated from any vol- 

 canic focus we are acquainted with, while a westerly propagation 

 of the ordinary vibrations rarely passes the great fault that marks 

 the line of active volcanic disturbance. In Japan, also, out of 

 about 480 shocks which are felt each year in that country, each of 



