April 2, 190S] 



NA TURE 



52: 



utility, riic chief feature is probably the careful provision 

 made for the distribution of voltage and current about 

 the building, the utmost flexibility in this respect 

 being essential for the varied purposes of test and 

 research. 



The building — mainly on one floor — comprises one large 

 bay (Fig. i) for machines and alternating current test 

 work, two parallel rooms of half the area for heavier test 

 work and resistance and direct-current work respectively, 

 with offices and workshops beyond. The photometry 

 section, on two floors, runs at right angles to these on 

 the east, .^bove are the rooms for the photometric 

 measurements, with a 90-feet track for arc-lamp work ; 

 the ground floor provides accommodation for life tests. 



I'iG. 3. — Water cooled rtguI.^ting resistances — capacity 6000 ampei 



and is already largely occupied with the specially designed 

 life-test racks necessary to cope with the probable demand 

 to which reference has been already made. The results 

 of the work on light standards at the laboratory since 1903 

 were laid before the Institution of Electrical Engineers by 

 Mr. Paterson in December, 1906, in a paper which gained 

 an institution premium, and much time has been devoted 

 during 1907 to work on the pentane standard, while the 

 photometry of differently coloured lights is also receiving 

 attention. 



The instruments for alternating current standard work 

 occupy the centre of the main bay (Fig. i) ; on the right, 

 under a platform to screen off light, are the two standard 

 electrostatic voltmeters, reading up to 400 volts, on two 



NO. 2005, VOL. 77] 



appro.ximately circular scales 26 feet in length, with am 

 accuracy of i part in 10,000. Outside the building, on 

 the opposite side of the main bay, is a small, entirely 

 detached, fire-proof high-tension transformer house, to be 

 occupied by the 100,000-volt transformer, with the aid of 

 which it is proposed that Mr. Rayner should continue the 

 valuable researches on insulating materials already pub- 

 lished. Twelve-inch ducts carry the high-tension current 

 into the large bay. 



Fig. 2 gives a general view of an instrument testing 

 station — or testing bench — at the east end of the large 

 bay (see Fig. i). The bench part of the stand in front is 

 arranged as a cupboard with glass top, in which instru- 

 ments of horizontal type can be tested at any tempera- 

 ture ; for other purposes the glass can be 

 covered with teak lids. The back compartment 

 il. contains heating lamps and a fan for carrying 



M the heated air to any part of the station, the 



'" upper part being arranged so that it can be 



covered with a thin celluloid cover. Above the 

 station may be seen the main heavy current leads. 

 In Fig. 3 are shown the water-cooled regulating 

 resistances employed for heavy current work, of 

 fiooo amperes capacity. 



The resistance room, in charge of Mr. Melsom, 

 contains arrangements for all high and low 

 resistance work, except that on ultimate 

 standards ; for tests on cables, insulation testing 

 sets, &-C., and for dry-cell testing. For accom- 

 modating accumulators under test a small build- 

 ing has been erected outside the north wall. 



Mr. Paterson and his collaborators have given 

 the utmost attention to all detail throughout the 

 building, the benefit of which will doubtless be 

 felt as the work increases. 



Although the development of the laboratory 

 since 190 1 has been rapid, it is clear that even 

 now i-t has but barely reached its most active 

 period of growth. The need and the value of the 

 services it can render become progressively moro 

 apparent, and Dr. Glazebrook's able administra- 

 tion and untiring energy may be expected to pro- 

 duce even greater, if perhaps not so obvious, 

 advances in the next seven years. 



THE NORTH SEA FISHERIES 

 INVESTIGATIONS. 



V\7 HEN the British Government in 1902 under- 

 took to cooperate with other countries 

 bordering on the North Sea in an investigation 

 into the fisheries of that region, it delegated its 

 share of the work in the north to the Scottish 

 Fishery Board and in the south to the Marine- 

 Biological Association of the United Kingdom. 

 The latter has now issued its second report upon 

 the work done by its naturalists and hydrographer 

 covering the period 1904-5. 



Four papers are included, and the first is by 

 Dr. Wallace on the age and growth-rate of plaice 

 in the southern North Sea, and is the result of 

 the application of a method of determining the 

 age of the fish by the otolith or " ear-stone." 

 Various attempts have been made to determine 

 the age of fishes. The scales furnish some evidence, but 

 in most cases, at any rate, they are hard to read. The 

 otolith method, on the other hand, is easy, and much more 

 rapid than the scale method. 



The otolith shows on its surface a series of concentric 

 rings alternately light and dark, and Reibisch in i89<> 

 found that each light ring represented the growth of the 

 otolith during the summer, while the dark rings repre- 

 sented winter growth. There seems to be no difference in 

 structure in the alternate rings, the different appearance, 

 being produced entirely by a difference in the density of 

 the substance. In the light opaque rings the particles 

 are more closely packed, while in the dark more or less 

 transparent rings the particles are farther apart. Since 



