TABLE VII.

DAILY DIETARIES.

Quantities of Nutrients and of Potential Energy in Nutrients.

The food of poorly-paid laborers in England, France, and Germany is thus seen to be deficient in nutrients.

The dietaries of peasants in Lombardy, who live upon corn meal, were very deficient, especially in protein; they suffer terribly from a disease called pellagra. It is found that when they have, along with. the corn meal, other food which supplies the lacking nutrients, the disease speedily disappears. The food of well-to-do English, French, and German mechanics and laborers was fully up to the standard,

while the ration of the German soldier for times of hard marching and hard fighting was considerably in excess of this standard. The results of the examinations of a number of American dietaries were given along with the European ones. The most striking feature was the large amount of nutrients which they uniformly contained. The amount of nutrients in the food of the French Canadians in Canada, in that of the same class of people when they had come to Massachusetts and worked in the factories; in the food of the Irish, German, and American factory operatives in the factories of Lowell, Lawrence, Lynn, Holyoke, and other places in Massachusetts, and in that of other people in Massachusetts and Connecticut, were illustrated in detail, the figures being based largely upon statistics collected by the Massachusetts Bureau of Statistics of Labor. There were no cases in which the quantities of nutrients did not come up to the European standard referred to. The majority largely exceeded this standard, so that the potential energy in the food supplied to mechanics, factory operatives, and laboring people in New England, as indicated by these dietaries, was in no case less, while in a number it was fifty or one hundred per cent more than in the European standard. The data at hand make it appear that not only well-to-do people, but the laboring classes, and even those whose income is relatively small in Massachusetts and Connecticut, are very bountifully provided with nourishment.

Two important inferences are to be drawn from these facts. One is that the food of people in moderate circumstances, as well as that of the rich, is apt to be very uneconomical pecuniarily, the materials being purchased at a much larger cost than is necessary. This superfluous expense is due in part to purchasing excessive amounts of food, and in part to the uneconomical selection of food materials. One of the worst phases of this bad economy is found in the habit of throwing away large quantities of food material. Of all civilized men the American is, perhaps, the most wasteful; and of the ways in which his wastefulness manifests itself, one of the chief is in his use of food. Another inference and one of perhaps even more importance—is that we are very much addicted to over-eating, a habit which is doubtless fraught with great injury to health. At the same time it is very probable that there is an important connection between the bountiful food of the American workingman and the large amount of work which he accomplishes. This particular question calls for fur

ther study. Doubtless the results of such investigation, rightly conducted, would throw very important light upon the problem of the ratio between wages and production.

Reference was also made to the food of the poor in Boston and other places. It was insisted that the people of the poorer classes are really least economical of all in their purchase and use of food, and that the instruction of the poor, and of people in moderate circumstances, in the elements of food economy, would be one of the most excellent ways in which knowledge may be utilized and charity exerted. One of the fortunate signs of the times is found in the work done in this direction in some of the schools in Boston, and in such work as that of Mrs. Richards in the Institute of Technology. The fact that these important problems are being taken hold of, and the results of scientific research applied in the ways mentioned, is extremely gratifying.

The meeting was brought to a close by a vote of thanks to the speaker.

MEETING 348.

The Micro-Membrane Filter.

BY PROF. W. R. NICHOLS.

The Creque System of Defecating, Storing, Circulating, and Employing Water for Domestic Purposes.

BY MR. ALLEN P. CREQUE.

The 348th and annual meeting of the SOCIETY OF ARTS was held at the Institute on Thursday, May 13th, at 8 P. M., President Walker in the chair.

After the reading of the minutes of the previous meeting, the Nominating Committee presented their report, and officers were elected for the ensuing year.

The report of the Executive Committee was read, and ordered placed upon the records.

The Meteorological Committee then reported through its chairman, Prof. Wm. H. Niles:

REPORT OF THE METEOROLOGICAL COMMITTEE.

Prof. NILES said that the specific duties of the committee during the year had been few beyond the ordinary inspections of the Boston signal station, and reporting upon its uniformly good condition. The committee had, however, co-operated with others who were seeking to advance the study and practical application of meteorological science, and some noteworthy improvements had resulted. A too common use of the term local, as applied to rains and snows in the weather " indications," had been criticised, and the desired change had been secured. Also an important change in the dangerous wind signals had been determined. The chairman spoke of the frequent misinterpretation of the cautionary signal, and explained the significance of the flags being introduced. He said that the red flag, with a black center, is to be continued as a cautionary signal; but, instead of being displayed whenever there is a probability of a wind having a velocity of twenty-five miles per hour, it will hereafter signify that a wind of at least thirty-five miles per hour is anticipated. As a wind of given velocity may, at a certain locality, be a source of danger if it blows from a certain direction, and may not be a dangerous wind if coming from some other quarter, it becomes desirable that the probable direction of the wind be indicated. Hence a direction flag is to be displayed upon the same staff with the cautionary flag. A diagram was used to illustrate how the arrangement and relative position of the two flags may clearly indicate the quadrant from which the wind is expected. It is to be hoped that by this method the value of the warnings will be considerably increased.

The finely-equipped meteorological station upon Blue Hill, constructed and maintained by Mr. A. Lawrence Rotch, is giving valuable aid to the Signal Service, and gathering important data for the study of the climate of the region of Boston.

The New England Meteorological Society is successfully conducting observations upon temperature and rainfall in about one hundred New England towns. Prof. Upton, of Providence, is employing some of the data thus obtained in making a detailed study of the important storms which traverse the territory. Two papers upon this subject, which have already appeared, show in a conclusive manner that it is

largely through a better knowledge of storm laws that practical meteorology may be advanced. The study of the thunder storms of last summer, under the direction of Prof. Davis, of Cambridge, has given promise of valuable results from the much-extended investigations to be made the coming summer.

THE MICRO-MEMBRANE FILTER.

The President then introduced Prof. W. R. Nichols, of the Institute, who described the Micro-Membrane Filter.

Prof. NICHOLS said: The so-called micro-membrane filter, which I bring before you this evening, is the invention of one Friedrich Breyer, of Vienna. This filter does not claim to exert any chemical effect upon the water, but relies for its efficacy upon the excessive minuteness of its pores through which the water must pass.

The material employed is asbestos. The value of this material as a filtering medium is well known to chemists, and it is frequently made use of in the laboratory; but the material which we there use is not as fine or as elaborately prepared as that used in these filters. The asbestos is first carefully selected and ground in a mill. We all know how a sheet of mica may be split into thinner and thinner layers; in the same way the threads of asbestos may be split longitudinally into thinner and more delicate threads. Practically, this is accomplished by grinding the wet asbestos with about its own weight of crystallized carbonate of lime, the carbonate of lime being subsequently dissolved out with hydrochloric acid. The resulting asbestos pulp is then allowed to deposit upon cloth stretched in an apparatus so arranged that the pressure may be diminished beneath it, and the asbestos film, or membrane, thus produced is a very different thing from ordinary asbestos paper. While water will pass through the pores, the finest solid particles are arrested, the film being made very thin to facilitate the passage of the water.

[Drawings of the fibers of cotton, sponge, a thread of silk, a spider-web thread, and fibers of asbestos, magnified a thousand times, were exhibited on the board, showing very clearly the extreme fineness of the asbestos fiber.]

It is calculated that with only three superimposed individual layers of this asbestos film there would be in every square millimeter two and a quarter million pores, or openings, for the passage of water.