SECTIONAL TRANSACTIONS.— J. 395 



An old electric motor was loaded eccentrically and run at speeds from 12 to 20 

 revolutions a second, and the pneumograph records from subjects sitting in a chair 

 subjected to the resulting vibrations were taken. 



The records reveal marked changes in the amplitude, frequency and form of the 

 respiration curve and show that, at certain critical speeds, which the subject finds 

 ' very unpleasant,' breathing is at first very irregular but tends, with continuation of 

 the stimulation, to settle down into rapid, shallow breathing that in the opinion of the 

 subject is in unison with the vibration frequency of stimulation, and that changes to 

 deep, gasping breathing when the stimulation is stopped. 



The subjective reports contain reference to : — 



(a) Vibration of the body or its parts, changing in position and intensity with 

 changes of speed. 



(6) States of tension that, subjectively, make it possible to control or endure the 

 unpleasant bodily vibrations and accompanying emotional experiences. 



(c) Cutaneous sensations such as ' pins and needles,' ' tickling,' and ' cold.' 



{d) General physio-psychological effects as headache, dullness, dizziness, tiredness 

 and sleepiness. 



(e) Pulse and respiration effects as ' throb of temples,' ' throb of pulse,' ' the pulse 

 and breathing both being in unison with the mentally counted rhythm.' 



(/) Revival of unpleasant travel experiences, including marked fear of catastrophe 

 and travel sickness. Cold, sleepiness and fear are outstanding effects of certain 

 revolution frequencies and in all probability are attributable, in part at least, to a 

 partial deprivation of oxygen caused by the hurried, shallow breathing induced by tlie 

 critical speeds. The danger of such effects on motor drivers and air pilots needs no 

 emphasis. 



Mr. Eric Farmer. — A Consideration of the Frequency Distribution of 

 Certain Tests. 



The examination of the frequency distribution of certain intelligence and sensori 

 motor tests showed that those that were scored by the amount of a task done in a 

 given time had Gaussian {i.e. saddle-backed) frequency distributions, whereas those 

 that were scored by the time it took to do a given task had skew distributions with 

 the mode nearer the good tail than the mean is. Since it is better for the purposes 

 of correlation if the test scores are normally distributed, it is suggested that where 

 possible the use of time-scored tests should be avoided. 



Certain visual tests had J-shaped frequency distributions. Certain physiological 

 tests such as pulse rate, on the other hand, had normal Gaussian distributions. It is 

 suggested, therefore, that the J-shapedness of the visual frequency distributions may 

 be due to the fact that they measure the capacity of a sensory end organ, and not 

 because they are in the main physiological in character. 



Mr. H. E. 0. James. — Interference. 



Friday, September 5. 



Mrs. S. Isaacs. — The Relation between Thought and Phantasy in Young 

 Children. 



I. Watching the free play of a group of intelligent young children, three main 

 types of spontaneous activity can be made out (which, however, are by no means 

 sharply separated, but readily slip over one into another) ; (a) the practice of bodily 

 skills of all sorts ; (b) make-believe dramatic games ; and (c) direct curiosity as to 

 the why and the wherefore of physical objects, and of animals and plants, for their 

 own sake. This last is the main field in which relational thought develops. 



II. The relation between make-believe and active thought again seems to be three- 

 fold : (1) circumstantial, (2) conative, and (3) cognitive. 



(1) Imaginative play creates practical situations which often lead on to genuine 

 discovery, to verbal judgment and reasoning and to interchange of argument. 



(2) There is a profound conative nexus between thought and phantasy. The 

 psycho-analysis of young children has shown the importance of symbol-formation in 



