August 6, 1903] 



NATURE 



331 



THE MARINE BIOLOGICAL ASSOCIATION. 



'T'HE council of the Marine Biological Association, in 

 ■*■ the report for 1902-1903, presented to the annual 

 general meeting of the association on June 24, state that 

 the work of the association has been considerably 

 augmented in consequence of the fact that a commission 

 has been accepted from H.M. Government to carry out 

 in the southern British area the programme of scientific 

 fishery investigation adopted by the International Con- 

 ference, which met at Christiania in 1901. The work in 

 connection with these investigations is being carried out 

 in the southern part of the North Sea and in the English 

 Channel. In connection with the North Sea work, a 

 laboratory has been fitted out at Lowestoft, and the steam 

 trawler Huxley has been hired. Some difficulty was ex- 

 perienced in obtaining a vessel suitable for the work with 

 the funds provided by Government, but the council were 

 fortunate in securing the assistance of one of their members, 

 Mr. G. P. Bidder, who himself purchased the Huxley from 

 her former owners and let her upon favourable terms to 

 the association. Accommodation for the naturalists has 

 been fitted up in the old fish-hold of the trawler, and a small 

 laboratory has been built on deck. 



The investigations in the North Sea include a scientific 

 survey, by means of the s.s. Huxley, of the trawling 

 grounds between the east coast of England and about 

 3° 30' E. longitude, in connection with which observations 

 are made on the nature of the bottom, the nature and 

 abundance of animal life living on the bottom and serving 

 as food for fish or otherwise, the size and weight of the 

 fishes caught, the food of the more important fishes, the 

 condition of the fishes as regards sex, maturity, or spawn- 

 ing, and the temperature of the sea at surface and bottom. 

 A simultaneous survey is being carried out of the regular 

 fisheries on the trawling grounds, with the assistance of 

 reliable masters of commercial fishing vessels. Experi- 

 ments are also being made on the migrations of fishes, by 

 marking and liberating fishes in large numbers over wide 

 areas. These experiments are designed to throw light on 

 the extent and direction of the seasonal and other migra- 

 tions of food-fishes at different stages of their growth, 

 particular attention being paid to the migrations of under- 

 sized flat-fish, and also to give an indication of the per- 

 centage of fish on the trawling grounds actually caught 

 by the trawling fleets from one year to another. In 

 addition to the above lines of research, special investi- 

 gations are to be made on the rate of growth, age, 

 fecundity and racial varieties of fishes, on the abundance 

 of floating fish-eggs, and on the variations in the size and 

 weight of fish landed at the various fishing ports through- 

 out the year. 



I'P to the middle of June the Huxley completed twelve 

 scientific trawling voyages in the North Sea. More than 

 34,000 fishes have been measured, the animal life of the 

 bottom has been systematically studied from the point of 

 view of distribution, and the food-contents of about 3000 

 fishes have been examined and determined. Plaice have 

 been marked and liberated in different parts of the North 

 Sea. In November and December a number of small flat- 

 fish were marked on the grounds west of the Borkum Reef, 

 and the results obtained are already of great interest and 

 importance. They indicate that during December and 

 January there was a marked migration southwards and 

 westwards of the small plaice previously congregated on 

 the inshore grounds of the northern and western coasts of 

 Holland, the distances travelled being in many cases quite 

 unprecedented, viz. from one hundred to one hundred and 

 sixty miles in six weeks or two months. More than 10 per 

 cent, of the fish liberated have already been recovered. 



The English portion of the international scheme of hydro- 

 graphic and plankton observations, the execution of which 

 has been assigned to the Marine Biological Association, is 

 to be carried out in the western half of the English Channel. 

 These investigations have for their object the study of 

 the seasonal changes which take place in the physical and 

 biological conditions prevailing over the entire region 

 covered by the international programme, though more 

 particularly directed to a study of the waters entering the 

 North Sea from different directions. They are designed to 

 determine (i) the origin, history, and physical and bio- 

 logical characters of the water found in each locality at 



different seasons of the year and at corresponding seasons 

 in different years, changes in which must necessarily have 

 a profound influence upon the distribution and abundance 

 of the fish-life in the sea ; and (2) the variations which take 

 place in the floating and swimming organisms (plankton) 

 which constitute the fundamental food-supply of the sea. 



The investigation is being carried out (i) by means of a 

 series of quarterly cruises made simultaneously over the 

 whole area by the vessels of the participating countries, as 

 a result of whioh a thorough knowledge, based upon the 

 most accurate available methods, is obtained of the con- 

 ditions prevailing at all depths at certain fixed stations, 

 together with a less detailed knowledge at intermediate 

 points ; and (2) by observations, more especially of the sur- 

 face conditions, at as many points as possible during the 

 time intervening between the seasonal cruises. 



Complete series of observations at twenty stations in the 

 P'nglish Channel were obtained during the first fortnights 

 of February and May. 



The ordinary work of the association has been carried 

 on at the Plymouth Laboratory during the year. Work 

 on the detailed record of the Plymouth fauna has been con- 

 tinued, the trawling experiments in the bays on the south 

 coast of Devon have been completed, and a considerable 

 number of naturalists have made use of the laboratory for 

 their special researches. The statement of receipts and 

 expenditure for the year shows a deficit of 117/. is. 



THE PARSONS STEAM TURBINE. 



'X'HE recent launching of the cross-channel turbine- 

 -*■ steamer, the Queen, to which reference was made in 

 our issue of July 2 (p. 209), has directed attention to the 

 efficiency of turbine engines for many purposes. An ideal 

 engine is one which has only one rotating part, and in 

 which the direction of movement is not varied. Engineers 

 have for many years recognised this fact, and much time 

 and money have been expended in their endeavour to perfect 

 a rotary engine. No practical success was, however,, 

 attained until 1884, when the Hon. C. A. Parsons, F.R.S., 

 placed on the market his first compound steam turbine 

 applied to driving a dynamo. Since then Mr. Parsons has 

 effected many andvarious improvements, until, at the pre- 

 sent time, the Parsons steam turbine is recognised by 

 engineers to be a thoroughly efficient and practical engine, 

 which, in the larger sizes, has attained an unprecedented 

 degree of economy in steam. In the latter few years, the 

 Parsons steam turbine has been applied to the propulsion 

 of ships with very satisfactory results, and bids fair, in 

 the near future, to supersede the reciprocating engine for 

 certain classes of vessels. 



A description of the Parsons turbine was given in Nature 

 several years ago (vol. Ixi. p. 424), with illustrations of 

 its parts. The turbine consists of a cylindrical case with 

 numerous rings of inwardly projecting blades. Within 

 this cylinder, which is of variable internal diameter, is a 

 shaft or spindle, and on this spindle are mounted blades, 

 projecting outwardly, by means of which the shaft is 

 rotated. The former are called fixed or guide blades, and 

 the latter revolving or moving blades. The diameter of 

 the spindle is less than the internal diameter of the cylinder, 

 and thus an annular space is left between the two. This 

 space is occupied by the blades, and it is through these 

 the steam flows. 



In the arrangement of turbine machinery as adopted in 

 the turbine Channel steamer the Queen, there are three 

 turbines, viz. one high pressure in the centre of the ship 

 and two low pressure, one on each side of the ship. Each 

 turbine drives a separate shaft, with one propeller on each 

 shaft, three in all. Inside the exhaust casing of each of 

 the low pressure cylinders a reversing turbine is fitted. 

 In ordinary going ahead, the steam from, the boilers is^ 

 admitted through a suitable regulating valve to the high 

 pressure turbine, and after expanding about 5-fold, it then 

 passes to each of the low pressure turbines in parallel, and 

 is again expanded in them about 25-fK,Id, and then passe* 

 to the condensers, the total expansion ratio being i2i;-fold. 



The Queen is the third passenger vessel built by Messrs. 

 Denny and Brothers fitted with the turbine system of pro- 

 pulsion supplied by the Parsons Marine Steam Turbine Co., 



NO. 1762, VOL. 68] 



