RECORD OF TESTIMONY AND STATEMENTS IN RELATION TO 151 



NECESSITY FOR DISTRICTING PLAN 



Artificial illumination in office buildings 



There is a direct relationship between the growth of bacteria and the 

 quantity of light. The conditions on Cedar Street have changed greatly 

 since the construction of the Equitable Building, this building cutting off 

 75 per cent of the natural light from the north side of the street. This 

 makes it necessary for the individuals in these offices to use artificial light 

 practically every working day in the year. 



In looking over the direct injuries resulting to workers from the use 

 of artificial light I found that a very large per cent of them are suffering at 

 the present time from eye strain to a marked degree. In some instances it had 

 generated nervous and hyper-nervous conditions, symptoms especially mani- 

 fest in the afternoon, between the hours of four and five o'clock. The lack of 

 light was just as demonstrable as the use of too much light. This was especi- 

 ally the case where electrical installations had been badly placed. I have dis- 

 cussed this subject with many physicians of the city and that is their 

 general opinion too. I have conferred with them especially with regard 

 to light, and they have stated to me that the number of cases of eye strain 

 with the resulting use of glasses in the City of New York, has increased in 

 the last five years almost 30 per cent and in some instances even as high 

 as 50 per cent. 



It is possible by artificial means to approximate conditions of day light 

 in office buildings, but whether it is commercially possible I do not know. 

 If seems to me it is commercially impossible at present. I know there is a 

 glass which cuts off approximately 85 per cent of the artificial light, but the 

 quality of the light when finally discharged approximates daylight very 

 closely. From the point of view of eye strain natural light is better than 

 artificial light. 



The experience of most physicians with regard to the use of artificial 

 illumination has been that little, if any, approaches the actual composition 

 of daylight. The newer lights, such as the tungsten and the nitrogen light, 

 are so intense in their rays that it is with difficulty that they are used with- 

 out really producing too much light. Now these rays have got to be modified 

 and diffused in such a way as to do away with the eye strain which follows 

 their use. Perhaps it is only a slight fancy on my part, but I believe that 

 some day, looking into the future, we will see that individuals who work 

 all the time under artificial light will gradually develop adaptability to that 

 kind of light at the cost of their adaptability to day light. 



I base this belief on the fact that employees in our factories manufac- 

 turing electric globes sit there and standardize globes continuously during 

 the first week, and suffer much from intense inflammation of the retina, the 

 interior portion of the eye, but that gradually goes away and the individual 

 accustoms himself to the new conditions. 



In natural light we understand the invisible rays to be the most active, 

 both chemically and bacteriologically. In artificial light we only have a 

 small per cent of these entering into its composition, and sometimes none 

 at all. On this account the bacteriocidal effect of artificial light is practically 

 nil. 



I found in one instance in one of our large banking houses, individual 

 efficiency was increased 25 per cent by changing the system of lighting and 

 the quality and kind of light. This was admitted to me by the office manager 

 himself. This was in the adding machine department. 



