308 REPORTS ON THE STATE OF SCIENCE.— 1915. 



but not universal, Saturday half-holiday may account for the compara- 

 tively fewer afternoon accidents there. But apart from these in the 

 English cotton industry (Table IXa.), the Belgian industries, and the 

 majority of single factories (Tables XVII. ft.), in all of which the 

 comparison is fair, the accident rate seems slightly lower in the after- 

 noon than in the morning. As regards output, there seems no general 

 rule, and the question will have to be considered under the different 

 varieties of work and conditions discussed in Section V.b. 



We have assumed that the break between the two main spells is 

 of an hour's duration. A clear exception to this is recorded, however, 

 in Table XXII., where only half-an-hour is devoted to lunch. The 

 result seems to be a very low accident rate in the hour immediately 

 following the half-hour break, but after that an extremely rapid and 

 confmuous increase up to the last hour of the day, when half as many 

 accidents again occur as in any hour of the morning. It is interesting 

 to compare this curve with Miss A. M. Anderson's evidence before 

 the Physical Deterioration Committee to the effect that ' in certain 

 industries where it is the custom to allow only half-an-hour in the 

 middle of the day for food very serious results are produced — in 

 London, for instance — in the dress trades.' 



But comparing the different hours of one spell we find in our 

 tables variations up to 25 per cent, in the output, and almost up to 

 300 per cent, in the accidents (see Table IX. a. Cotton). This 

 latter figure is all the more remarkable since, as was pointed out in 

 Section II., those accidents that are due solely to mechanical causes are 

 not likely to vary in amount throughout the day. 



The actual course or direction of the variations, however, differs 

 very much for accidents and output respectively. 



In the case of otitput there is in every table an increase of the 

 second over the first hour of the spell except for a very slight decrease 

 in Table IV. (Machine Sewing) in the afternoon. This almost general 

 increase is as much as from 24 to 38 in soldering. Table III. Col. 1 

 (a.m.), and from 85 to 106 in Hand Chocolate-covering, Table II. 

 Col. 2 (a.m.) 



After the second hour of each spell there is generally a gradual 

 decrease till the last hour, though in the third hour the output may 

 be yet higher than in the second. In the case only of Apparatus- 

 covering (Table II. Col. 1), and of the Cotton Trade (Table VII.), is the 

 last hour's output higher than that of the second hour of one of the 

 spells, though in stamp-pressing (Table VIII.) the last half-hour is 

 considerably higher in both spells. This general decrease is particu- 

 larly marked in the case of soldering (morning spell Table IV. Cols. 1 

 and 2), where the second hour's output was 38'42 at Jacob's and 52'4 

 at Cadbury's; the fifth hour's output only 29-74 at Jacob's and 43"7 

 at Cadbury's. 



The same general characteristics mark the course of the spell in 

 the only other records taken of the hourly distribution of output 

 made previous to this, those of Prof. Pieraccini, of Florence (Index 

 D5), and of Dr. Howard Marsh, of New York (Index D6). 



Dr. Pieraccini studied six typesetters in one shop and four in 



