February 13, 19 13] 



NATURE 



651 



EYESIGHT AND TYPOGRAPHY.'^ 



T^HIS report of the British Association Com- 

 -L mittee on the influence of school-books upon 

 eyesight is full of interest. Its value depends 

 chiefly upon the report of the oculist subcom- 

 mittee, which was composed of Messrs. Priestley 

 Smith, H. Eason and N. Bishop Harman. Advice 

 upon the technical and trade aspects of printing 

 was given by competent experts. 



The subcommittee's report is valuable from the 

 immediate point of view of school-books and also 

 from the point of view of the reading of printed 

 matter in general. Considering the enormous 

 importance of reading and writing to the general 

 public and the large place they occupy in daily 

 life, it is remarkable that so little attention has 

 hitherto been devoted to the physiological and 

 hygienic features of the subject. It would have 

 been a gracious act for the subcommittee to have 

 expressed its indebtedness to the researches of 

 Javal, an indebtedness which is unmistakable. 

 With few exceptions the report recommends the 

 principles advocated by Javal, and the authors 

 have, perhaps wisely, refrained from any experi- 

 mental researches on their own account. The 

 subject is full of complications, physiological and 

 psychological, and the recommendations made are 

 as good as can be expected in the present state 

 of knowledge. 



At the outset of the section on the hygienic 

 requirements the right note is struck in em- 

 phasising the fact that the reader recognises 

 whole words and phrases at a glance. This state- 

 ment expresses the essential difficulty of the 

 scientific investigation and regulation of printing. 

 Too much stress cannot be laid upon the fact 

 that the canons of visihility of individual letters 

 do not apply directly to the far more complex 

 problem of the legibility of letter groups in words 

 and phrases. It is rightly pointed out that the 

 upper half of a word or letter is usually more 

 important for perception than the lower half. We 

 would emphasise the point more strongly. It is 

 the fundamental factor in legibility, as is easily 

 proved by reading with the lower half of the line 

 covered by a card. Hence we think that the 

 suggestion made to give more distinctive character 

 to the lower half of a larger proportion of letters 

 is unsound. 



The general evolution in the shapes of printed 

 letters has been in the direction of increasing the 

 predominant features of the upper halves, so that 

 more letters extend above the line than below, 

 the extension above the line has increased, whilst 

 that below has been curtailed, and so on. These 

 tendencies are in favour of legibility and should 

 not in our opinion be tampered with. For the 

 same reason we are astonished at the statement 

 that "uncial Greek may be recommended as being 

 easv to read (see supplement)." The supplement 

 gives two examples, one in 12-point Porson Greek, 



1 Report on the Infli 

 of the British AsisociatJon. prese 

 obtainaHle from the British A 



f School-bool«<; upon Kyesight by a Committee 

 the Dundee Meetinc. iqi2. Copies 



NO. 2259, VOL. 90] 



the other in uncial Greek on long primer body. 

 A glance suffices to show that the former is much 

 more legible. 



Owing to the complexity of the correlation of 

 the physiological and psychological factors in read- 

 ing, such details as the best dimensions of letters 

 and spacing, length of lines and their separation, 

 and so on, are at present matters of compromise. 

 The committee does not give any explicit scientific 

 reasons for the faith that it has, but the typo- 

 graphical table and the rules laid down are 

 eminently sensible. The small type used in Bibles 

 and prayer-books is more than a matter of regret ; 

 we should like to have seen it more severely 

 condemned. The remarks on the thorny question 

 of atlases are very good. 



We hope that this report will have a widespread 

 influence. It contains much sound advice not 

 only for those who deal in school-books but for all 

 authors and publishers. 



INVESTIGATION OF ATMOSPHERIC 

 POLLUTION. 



THE Committee for the Investigation of 

 Atmospheric Pollution, appointed at the 

 International Smoke Abatement Conference and 

 Exhibition held in London last March, has held 

 three meetings in London and has just published 

 what may be regarded as an interim report. 



This report states that after careful considera- 

 tion of all the various methods that have been 

 suggested or tried for measurement of the 

 impurities of the atmosphere, that employed for 

 The Lancet investigation of the soot and dust-fall 

 of London in 1910 has been selected as the 

 simplest, and the one most likely to yield satisfac- 

 tory results under the conditions which will 

 govern the observations that are to be made. The 

 method is based upon the use of an apparatus 

 resembling an enlarged rain-gauge, with a catch- 

 ment area of 4 sq. ft. This gauge receives all 

 the dust and soot that falls by its own weight 

 or is carried down by the rainfall during the period 

 of its exposure, and on examination of the water 

 which collects in the bottle attached to the 

 apparatus, the amount of total suspended matter, 

 tarry oils, soot, &c., can be determined. 



A circular letter has been sent out by the 

 committee to all the more important city and local 

 authorities in the L'nited Kingdom, asking for 

 their cooperation in the application of this method 

 of observation in the districts over which they 

 have administrative powers. This circular has 

 met with a most gratifying response. The 

 authorities of a large number of important cities 

 have already signified their intention of com- 

 mencing observations on the lines suggested by 

 the committee, and many other authorities are 

 only waiting for further details before promising 

 their support to the movement and cooperation 

 in the work. Birmingham, Bradford, Leicester 

 and Newcastle are the most important of the 

 cities that have definitely promised their support ; 

 but there is no doubt that Glasgow, Liverpool, 



