November 26, 1908J 



NA TURE 



always met with success. Certain lakes possessing all 

 the obvious biological and physical requirements have been 

 repeatedly planted without result, and it has been but 

 recently 'determined, through the work of Prof. E. A. 

 Birge, that the failure is due to peculiarities of the gaseous 

 content of the water. In a paper on the gases dissolved 

 in the waters of Wisconsin lakes. Dr. Birge illustrated 

 his studies, which are of the highest value to fish culture. 



A paper on the utilisation of sea-mussels and dogfish as 

 lood, presented by Dr. Irving A. Field, opened a very 

 general discussion on a subject which appealed to both 

 the biologists and the practical fishermen. During recent 

 years the horned dogfish (_Sqiiali<s acantbias) has been 

 e.Ktremely destructive to fish and fishing on the coasts of 

 Canada ' and New England, while the smooth dogfish 

 {Mustehis cams) is a perennial menace to the lobster. In 

 Canada oil and fertiliser works have been established for 

 the purpose of supplying a market and encouraging the 

 destruction of the dogfish, and Prof. Prince is of the 

 opinion that they have to some measure decreased in 

 numbers. 



Dr. Field's experiments have demonstrated that the 

 smooth dogfish, salted and dried, makes a product closely 

 resembling the cod, and in a fresh condition it is not 

 inferior « texture and flavour to halibut ; the horned dog- 

 fish, being more oily, is better adapted for tinning. Mr. 

 Fryer stated that the equally destructive dogfish of the 

 English coasts had been placed on the markets by the 

 fishermen, and while it wa^ unobjectionable as to quality, 

 it met with prejudice on account of its name, a difficulty 

 which also confronts the exploitation of dogfish as food 

 in the United States and Canada. An euphonious name, 

 not deceptive in character, would assist greatly in con- 

 verting a fishery menace into a valuable product and 

 important source of cheap food supply. The practical 

 difficulties confronting the utilisation of these fish are 

 being made the subject of inquiry by various technical 

 bodies in the United States and Canada. 



A communication from the Rhode Island Commission 

 of Inland Fisheries, in reference to the effects of gun- 

 fire on schools of fishes, developed a difference of opinion 

 between the scientific men and the practical fishermen. 

 The latter declared that the heavy detonations from cannon 

 drive the fish away from the coast, but the results of 

 experiments at Woods Hole, as recounted by Dr. Sumner, 

 indicated that mackerel and other surface-living fishes were 

 but little disturbed by either gun-fire or the noises made 

 by, boats using explosive engines. The investigations of 

 Dr. Parker at the fisheries laboratory prove that certain 

 fishes are influenced by sound stimuli as distinguished from 

 the grosser mechanical vibrations of the water, but that 

 their sudden movements of alarm are dictated by sight 

 rather than by hearing. 



Eighteen corporations and individuals interested in the 

 fisheries offered prizes for contributions on special subjects, 

 and of these seven were unawarded, either because the 

 papers submitted did not satisfy the strict conditions of 

 the award or because they did not conform to the standard 

 of merit imposed by the international jury of awards. Two 

 awards were made to Prof. A. D. Mead for the papers 

 abos'e-mentioned, two to Dr. H. F. Moore for papers on 

 the sponge fisheries and on growing sponges from 

 cuttings, one to Mr. Dwight Franklin for the best method 

 of preparing fishes for museum purposes, one was divided 

 between Dr. F. A. Lucas and Mr. R. W. ' Minor, for 

 papers on the best plan for an educational exhibit of 

 fishes, one was given to Mr. Chas. H. Stevenson for the 

 paper above alluded to, one to Mr. Paul Reighard for 

 the best plan to promote the white-fish production of the 

 Great Lakes, one to Prof. Jacob Reighard for the best 

 methods of observing the habits and recording the life- 

 hislories of fishes, one to Mr. Chas. G. .Atkins for a paper 

 on foods for use in rearing young salmonoids, and one to 

 Mr. John J. Solomon for a process for preserving the 

 pearl fisheries and increasing the yield of pearls. 



Many papers of much practical and scientific merit were 

 submitted, but not read for lack of time, but they will be 

 published in the proceedings of the congress. The fifth 

 congress will be held in Rome in iqii, the year of the 

 semi-centennial of the Italian Federation. 



NO. 2039, VOL. 79] 



T 



PSYCHOLOGY OF PLEASURE AND PAIN. 



HE last two numbers of the Psychological Review- 

 (July and September) have contained important 

 articles by Prof. Max Meyer, of the University ol 

 Missouri, on the nervous correlate of pleasantness and 

 unpleasantness. In the former the author brings out the 

 contradictory character of the present views of psycho- 

 logists on this subject, and in the latter proposes a theory 

 that he believes accords with all known facts and gives 

 proportionate weight to the various aspects of the ques- 

 tion upon which his predecessors have dwelt too ex- 

 clusively. The clearest opposition has hitherto been 

 between the psychologists, who hold that pleasantness and 

 unpleasantness are merely weak (and therefore badly 

 localised or entirely unlocalised) forms of the sensations^ 

 which at a higher degree of intensity become respectively 

 sexual sensation and pain, and those who, denying their 

 substantive status, regard them merely as aspects or 

 " tones " of sensational processes. 



Prof. Meyer's theory is of a different type altogether, 

 and is based upon the concept of an hierarchy of reflex arcs 

 or a "centralisation by degrees." Let A and B be two 

 sensori-motor systems of neurons relatively independent, 

 but having at least one connecting neuron in common. It 

 is always possible for these to merge into a more cornplex 

 sensori-motor system, C. The marks of this higher 

 organisation will be (i) that stimulation of a sensory point 

 of either A or B mav produce simultaneous reactions at 

 motor points both of A and B : and (2) that simultaneous 

 stimulation of sensory points of both A and B may pro- 

 duce a reaction at a motor point of A or B only. In the 

 case of such a system, if the subsystem A is functioning 

 a strong stimulation of subsystem B will produce a de- 

 crease in the intensity of the current in A (drawing it off, 

 in fact, towards motor points of B), while a gentle 

 stimulation of B will merely increase the current setting 

 towards motor points of A. The decrease or increase in 

 the flow through system A, due to the action of B, is the 

 nervous event which will be experienced as unpleasantness 

 or pleasantness respectively. For example, the_ slight 

 degree of pain produced by scratching after an insect's 

 bite is rather pleasant, for it actually increases the energy 

 of the scratching process. If, however, the pain becomes 

 too intense, its own typical reaction is set up ; energy is 

 drawn off from the scratching process, and unpleasantness- 

 is felt. , 



It follows on this theorv that pleasantness and un- 

 pleasantness are attributes of the relatively more complex 

 psychophysical functions, and, therefore, that their highest 

 intensity ' may be expected to accompany intellectual 

 activity— a result which the author claims as a powerful 

 piece of evidence of the superiority of his doctrine over 

 that which would regard them as " feeling tones " of 

 sensations. 



SCIENTIFIC EDUCATION OF NAVAL 

 ARCHITECTS}- 

 TT has occurred to me that an appropriate subject for 

 ^ the address, \vhich it is my duty to deliver as chair- 

 man of the council, may be found in a brief account of 

 the methods adopted for' the education of naval architects 

 in this country during the past century. I venture to 

 hope that, ap'art from its particular interest for those 

 engaged in shipbuilding, the narrative may have some 

 value and attraction for those interested in technical educa- 

 tion generally, and that it may throw some light on 

 problems of 'higher technical education which still await 

 solution in this country. . 



In 1806 the Commission of Naval Revision reported m 

 regard to the principal shipbuilding officers of the Royal 

 Navy. There is evidence that outside the Admirahy service 

 the standard of professional attainment amongst British 

 shipbuilders was then low. As practical ship-carpenters^ 

 they excelled; their ships were "well and truly built, 

 strong and durable. As ship-designers they depended on 



1 From an address delivered before the Society of Arts on November iS 

 bv Sir W. H. White, K.C.B., F.R.S., chairman of the Council of the 

 Society. 



