830 



NATURE 



[February 24, 192 1 



him realise tliat tlie value of a digit depended upon 

 its position, and that the zero was simply a shorthand 

 symbol for an empty place. His coloured thinking 

 satisfied me that 1 had completely succeeded, and 

 that the cipher o was really nothing to him. 



I note that Miss A. M. sees 20, 30, 40, etc., coloured 

 as 2, 3, 4, etc. ; but since, apparently, 20-29 are 

 coloured as 2, 30-39 as 3, and so on, there is no such 

 inference possible in her case. It would, however, 

 be of interest to learn whether she sees o coloured or 

 not. 



There was one exception to this nonentity of zeros 

 in my son's mind; for he described 1000 as always 

 yellow, adding that "it ought to be black really [i.e. 

 the colour of i], but it is not ; that's the funny 

 thing; it does not come in proper order." My inter- 

 pretation was that a thousand seemed to him some- 

 thing so big' and important that it stood by itself 

 and rather out of relation to the lower numbers ; and 

 I suspect that, had he known it only as " ten 

 hundred," it would have been duly black. 



It will be observed that, although on the earlier 

 occasion he gave no specific colours to i and 2, yet 

 his colours for 10, 11, and 12 accorded pretty well 

 with the colours assigned on the second occasion to 

 1 and 2. Otherwise there is no discrepancy between 

 the two records. 



I obtained from him also the colours of the points 

 of the compass, of the names of various towns and 

 countries, and of sundry other names ; but too much 

 space would be occupied by the account and discus- 

 sion of these. He told me that "nearly everything 

 I can think of is coloured." 



My daughter similarly has coloured concepts ; but 

 she has also what I do not remember ever to have 

 seen described in anyone else until I read Prof. 

 Harris's letter, and that is coloured tastes. I think, 

 too, that tastes are more strongly coloured for her 

 than for Miss A. M. She has frequently, to our 

 amusement, spoken of things having "a mauve taste"; 

 and when we were discussing coloured thinking last 

 vacation she remarked that " of course all tastes are 

 coloured." 



Prof. Harris emphasises the normally hereditary 

 character of coloured thinking. A few words have 

 always been coloured for me, and in a vague and 

 misty wav many probably are ; but if I try to see 

 (mentally) what precisely the colours arc, I cannot 

 succeed. It seems rather as though some words had 

 polished or glittering surfaces, or a sheen, and 

 reflected light, while others were sombre and light- 

 absorbent. When I read Galton's book about thirty 

 vears ago I realised that I saw the numerals in a 

 psychogram. 



My wife, after declaring that coloured thinking 

 was utterly unintelligible to her, mentioned that, of 

 course, the vowels are coloured, and that she had 

 supposed they were for everyone, but that the con- 

 sonants are not. It appears, therefore, that my children 

 started from a slight, but twofold, hereditary tendency 

 to coloured thinking. Frank H. Perrycoste. 



Polperro, Cornwall, February 12. 



The Effects of Oil from Ships on Certain Sea-birds. 



Sir Arthur E. Shipley has recently directed 

 attention to the probable effects upon our fisheries of 

 the discharge of oil from ships into the sea. 1 should 

 like to refer to another side of this matter, viz. the 

 effects upon certain species of sea-birds. 



For our present purpose we may divide sea-birds 

 into three groups according to the number of eggs 



NO. 2678, VOL. 106] 



they hatch per season, and, further, in each group 

 we may distinguish certain species as divers. All, I 

 believe, are single-brooded. 



In the first group we have those species which 

 hatch a single egg each season, such as the petrels, 

 fulmars, sherewaters, and the razorbill, kittiwake, 

 guillemot, little auk, puffin, etc. In the second group 

 are the terns and the great northern and black- and 

 red-throated divers, usually hatching two eggs per 

 season. With the exception of the cormorant and 

 the shag. Group 3 consists of the more littoral 

 sijecies (chiefly Laridje), which produce three or more 

 eggs per season, and scarcely bear upon the present 

 subject. 



During the past five years large numbers of those 

 species which dive beneath the surface of the water 

 in order to obtain their food have been washed up 

 on the Fife coast and elsewhere dead or in a dying 

 condition and covered with a thick coating of oil. The 

 actual total of dead birds must be enormous. In one 

 day we counted more than 300 kittiwakes and almost 

 the same number of razorbills and guillemots, and 

 dozens of little auks and puffins, and this is of 

 frequent occurrence. On the west sands at St. 

 .*\ndrews in October last dozens of dead gannets in a 

 similar condition were washed ashore. Even ad- 

 mitting that these represent a concentration from a 

 great sea area, the oft-repeated occurrence indicates a 

 new factor of disturbance which is proving inimical 

 to a large percentage of these birds. If this continues, 

 or the disturbing factor grows more serious, the 

 possibility of the extermination of such species seems 

 not at all unlikely. 



It is a generally accepted biological principle that 

 the rate of reproduction of a species is a character 

 very slow to change, and in the case of slow breeders, 

 such as the species here referred to, any unusual 

 factor leading to a higher rate of mortality can only 

 lead to very serious consequences. 



Walter E. Collinge. 



The University, .St. .Andrews. 



The Annular Eclipse of the Sun on April 8. 



As the annular eclipse of the sun on April 8 next 

 may be of considerable interest to amateur observers, 

 I am preparing a list of observations which may be 

 made both within and without the region of an- 

 nularity, and also full instructions for making the 

 observations. Should any readers of Nature care to 

 suggest observations which might be made with small 

 telescopes and the equipment generally possessed by 

 an amateur, I should be very glad to receive their 

 suggestions. May I also add that I am proposing to 

 observe the eclipse from a point near the central line 

 (probably Benbecula, in the Outer Hebrides), and if 

 other amateurs would care to join me, would they 

 please communicate with me with the view of forming 

 a party? • J. Hargreaves. 



The Priory, Royston, Herts, February 2. 



A Rare Example of Melanism. 



I would like to record the occurrence of a rare 

 case of melanism. Mr. Carl Carinus, in Rhodesia, 

 sent me the complete skin and skeleton of an adult 

 female oribi. It was entirely black, without any 

 trace of white or red. The female was in the com- 

 pany of an adult male of normal colour. 



F. W. FiTzSlMONS. 



Port Elizabeth Museum, Port Elizabeth, 

 January 27. 



