In connection with the high percentage suffering from defective vision, only 11.5 per cent of those whose eyesight was subnormal wore glasses. But 2.35 per cent of those with defective vision had glasses fully correcting the defect; in 7.5 per cent the defect was partly corrected, and was not improved or made worse by the use of improper glasses in 1.67 per cent.

A faulty posture was extremely common among garment workers, especially males. The bad effects upon health of faulty postures are well known, as they predispose to pulmonary affections, including tuberculosis, hernia, displacement of the abdominal organs, digestive troubles, weak and flat feet, and constipation.

That the general condition of health of garment workers is by no means satisfactory is shown by the large number of those examined who had subjective complaints to make about the state of their health. About 70 per cent of all examined had such complaints, while only 30 per cent stated that they felt well. Pain of some kind was the most frequent complaint; digestive disturbances, such as dyspepsia and chronic constipation, came next. Some 10 per cent of the males and 25 per cent of the females complained of frequent headaches. Nine per cent of males and 4 per cent of females complained of weakness either general or of the extremities.

The investigation resulted in the making of recommendations to the joint board of sanitary control for the improvement of conditions under the board's jurisdiction. Stress was laid upon education as a means of improving the knowledge of personal hygiene on the part of the worker, the lack of which plays an important part in the causation of the defects and diseases noted in the examinations.

The complete report of this investigation has been published as Public Health Bulletin No. 71.

Hygienic conditions of illumination in shops of the women's garment industries.-In view of the fact that garment making involves the close and continuous use of the eyes, the hygienic conditions of illumination in such industries become of importance, especially in view of the high percentage of visual defects revealed by physical examinations in garment workers.

The conditions of illumination were studied in a group of 34 workshops containing 45 typical workrooms. All the shops visited utilized daylight illumination. In 23 per cent of the shops auxiliary artificial illumination at some working plane had to be habitually depended upon.

As garment making requires an illumination at least equal to that which should prevail in a well-lighted schoolroom, the minimum standard upon working planes was placed at 5 foot-candles in order to insure satisfactory working conditions. Taking this illumination as a standard, it was found that at a little over one-half the working planes at which photometric measurements were made the illumination failed to reach this standard. Generally speaking, machines received the best illumination, followed in order by finishing tables, pressing tables, buttonhole machines, cutting tables, and basting tables. In design departments, in which sample garments are made. up, the illumination was found to be more satisfactory than in the

general shop, thus showing that shop owners recognized the necessity of adequate illumination for the execution of careful work.

With a view to improving illuminating conditions in these shops recommendations were made to the joint board of sanitary control of the cloak, suit, and skirt and dress and waist trades. These recommendations are published in Public Health Bulletin No. 71.

Chemical composition of the air of workshops in the women's garment industries. In view of the extensive use of gas-heated pressing irons in the workshops of the women's garment industries, with the resulting possibility of the contamination of the air with poisonous amounts of carbon monoxide, careful studies of the composition of the air of a number of shops were made. A comprehensive study of the permeability to gas of the various kinds of gas hose upon the market was also undertaken, and studies were also made of the composition of the combustion products of gas-heated pressing irons. This work is now nearly completed and a full report will appear in the near future.

The combustion products of certain makes of gas-heated pressing irons were found to contain a considerable proportion of carbon monoxide, some of the analyses giving as high as 2 per cent of this gas. It is needless to say that the use of such irons in closely confined surroundings may readily produce symptoms of poisoning.

ILLUMINATION STUDIES IN GOVERNMENTAL DEPARTMENTS.

In conformity with the plan of the service to make a comprehensive investigation of the hygiene of illumination, studies were commenced in Washington, D. C., in the Federal buildings. During the spring a photometric survey was undertaken of the Treasury Building which has just been completed. In this survey rooms typical of every lighting condition in the building were photometrically surveyed and the relation of the illumination to the kind of work done studied. Besides studying the amount, character, and distribution of the illumination, studies are also being made of the vision of employees in the department. The employees have been classified according to the kind of eye work they perform, and data are being collected of the state of their vision in relation to their occupation.

Laboratory studies of the physiology of vision. In addition to the field work just mentioned, arrangements are being made for the conduct of laboratory studies of the action of light upon the eye. These studies will have for their object the adaptive function of the eye with relation to light of various wave lengths, the effects of infrared radiation upon the eye, the effects of ultra-violet radiation, the cumulative effects of radiation, and other problems.

TUBERCULOSIS IN RELATION TO INDUSTRIES.

The study of tuberculosis in relation to the industries in Cincinnati, begun in March, 1914, was continued throughout the fiscal year 1915, under the direction of Surg. D. E. Robinson.

10435°-15-4

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PUBLIC HEALTH SERVICE.

The following table gives the results of the examinations of employees made during the year:

The study was not limited to the industries alone, but was extended into other fields in an attempt to determine the most important causes predisposing to the high mortality from tuberculosis. The study included a survey of 138 families in which the board of health records showed there had been a case of tuberculosis, with a view to determining living and economic conditions and, if possible, the most common predisposing causes.

A study was also made of the cases of tuberculosis under treatment at the municipal tuberculosis hospital with the same end in view.

Studies were also prosecuted to determine the influence of climatic conditions, floods, population elements, immigration, and growth upon the tuberculosis death rate. The results of the above-mentioned studies, as well as the details of the investigation of tuberculosis in relation to the industries, will form the subject matter of a separate and more complete report.

Tuberculosis among prostitutes.-An examination for tuberculosis was made of the women in the segregated district of Cincinnati, 68 houses being visited and 317 inmates examined, of whom 27 were found presenting evidences of tuberculosis, 3 being open cases.

MINE SANITATION STUDIES.

Investigations of the occupational diseases connected with the mining industry and of mine sanitation, begun in 1914 in cooperation with the United States Bureau of Mines, were continued during the last fiscal year.

Attention having been directed to the prevalence of pulmonary diseases among the zinc miners of Jasper County, Mo., Passed Asst. Surg. A. J. Lanza was directed to make an investigation of sanitary conditions in relation to the zinc-mining industry in the Joplin district. A preliminary report by Dr. Lanza and Mr. Higgins, mining engineer of the Bureau of Mines, was made in December, 1914. Sanitary investigations of the mines were made with extensive sampling of air in underground workings for the purpose of determining the nature and amount of dust in suspension in working places. Physical examinations of miners were also made and vital statistics compiled from all available data. The report based on these studies was to the effect that pulmonary tuberculosis and silicosis were extremely prevalent among the miners of the Joplin district, the main etiological factor being a peculiar flinty rock dust with high silica content (95 per cent and more) found in what are known locally as "sheet-ground" mines. Other conditions favoring pulmonary disease were overwork, insanitary drinking devices in the mines, and unhygienic living conditions. It was also found that much, if not most, of the dust in the mines was unnecessary and due to carelessness or lack of knowledge of the harmfulness of dust on the part of miners and mine operators.

This investigation was resumed along broader lines in February, 1915, and is still being carried on. An educational campaign was inaugurated on tuberculosis, its nature and the important relation it bears, locally, to flint dust. Lectures were delivered, illustrated by lantern slides showing magnified particles of stone dust and by moving-picture films. Many of the mines were visited and short talks delivered to the miners during the noonday dinner hour, and every effort was made to arouse them to the dangers of dust breathing and the necessity of their cooperation in mitigating dust conditions.

Among the mine operators there was organized a sanitation and safety association for the purpose of promoting cooperation in the betterment of working conditions and instituting reforms, as far as practicable, in those methods of work that cause dust. This organization is active and thriving.

The State legislature, on the recommendation of the State mine inspectors, passed laws providing for the sprinkling of metal mines, prohibiting certain practices in mines that tend to cause dust, prohibiting common drinking devices underground, and providing for clean and adequate change houses.

This investigation is being pursued for the purpose of determining the actual relationship of silicosis to tuberculosis. The connection between industrial dust diseases and tuberculosis is becoming more and more apparent and offers a wide field for both investigation and reform. During April, 1915, the Public Health Service opened an office in Webb City, Mo., in the heart of the zinc mining district, for

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the physical examination of miners and the collection of statistics relative to the spread of infection among their families. Up to June 30 over 350 miners had been examined, more than half of whom showed definite signs of pulmonary disease. Sputum examinations are made whenever possible and a series of X-ray plates taken, which throw considerable light on the extent of dust injury to the lungs in these cases. This work will be concluded during the next fiscal year and a report made on these data, together with the protocols of cases.

STUDIES OF SANITATION OF STEEL PLANTS.

The investigation by Asst. Surg. J. A. Watkins of existing sanitary conditions in the metallurgical plants of the Pittsburgh district, referred to in the last annual report (p. 52), has been continued during the year.

To date investigations have been made in a number of plants employing approximately 34,000 men. The characteristics of the industry have been studied and an endeavor made to determine the mutual attitude between employers and employees. The steel workers have been studied as a class, and information relative to the age and race composition of the force, the food eaten, and the clothing worn in the mill has been collected and observations made on such personal habits as might affect health, particularly with reference to avoiding the health hazards incident to the occupation.

A survey of the steel works was made, which included the general sanitary condition of the plant, the character of the work, the amount required, and the conditions under which it was performed. The sanitary survey of the plant included the following: Drinking water; sewage and waste disposal; toilet facilities; bathing and washing conveniences; wash, change, and locker rooms; rest and lunch rooms. The character of the work was observed in order to determine whether it was of such nature as adversely to affect health.

The amount of work performed by these men was gone into in detail, the information collected being the total hours of duty per week and per turn, and in order to determine accurately the actual amount of physical exertion required, each occupation was studied separately. The total time on duty was divided into that time spent at physical exertion, at rest, and active, and a large number of stopwatch readings taken to determine what percentage of the total time on duty each constituted. The conditions under which the work is performed received special attention, the following subjects being investigated: Buildings, space, flooring, speeding-up and monotony, industrial lights, noise, vibration, working positions, illumination, suspended matter in the air, harmful gases, ventilation, temperature, and humidity. The temperature and humidity to which the steel workers are exposed was gone into in detail, several thousand psychrometric readings being taken. The length of each exposure was determined by a stop watch; the number of exposures on one turn determined and observations made at the time as to the character and amount of physical exertion required of the men while so exposed.

Before drawing conclusions as to what effect the employment or the environments alone had upon the health of the steel workers it was