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outside of this market are not graded and the same control is exercised over this milk as is given the grade B Pasteurized.

The maintenance of a supply of raw mixed milk is dependent upon our ability to identify the dairymen who, because of faulty methods of cooling or caring for their milk, or laxness in the care of their milking utensils, persistently produce milk containing a high bacterial content. This milk in turn contaminates all milk with which it is mixed in the storage vats, and at times may endanger the whole supply for either manufacturing purposes or for fluid milk distribution. The Breed method has been very useful in identifying these high count dairies, and in enabling us to inform the dairyman of the kind of milk he is producing and the purchaser of the kind he is buying

The samples for making the Breed examination are taken every two weeks from a well-stirred can of milk from each dairyman. These samples are caught in sterile vials as the milk is dumped. The vials are placed in a special rack surrounded by ice water and held at a low temperature until the smears are made. By means of a pipette, 0.01 of a cubic centimeter is transferred to a glass slide and smeared over a square centimeter of space. As a means of identification, the number of the dairy is placed above each smear. For convenience, 12 smears are placed on each slide. The smearing is aided by the use of a guide, which marks out the square centimeters, and which is used beneath the glass slide containing the smears. These smears are allowed to dry slowly and are then stained and read in the laboratory. The field of the microscope is calibrated to cover 300.000 of a square centimeter. Fifteen fields are generally counted, counting each clump or isolated bacterium as one. The bacteria are estimated and the milk graded as follows:

0 to 5 clumps or isolated bacteria in 15 fields denote good milk or less

than 100,000 bacteria per cubic centimeter. 6 to 25 clumps or isolated bacteria in 15 fields denote fair milk, or a

count from 100,000 to 500,000 per cubic centimeter. Over 25 clumps or isolated bacteria in 15 fields denote poor milk with

a bacterial content of over 500,000 per cubic centimeter, and is considered unsatisfactory and a source of danger on account of its contaminating influence on the good and fair dairies when mixed in the

storage vats. As a rule these glass slides are mailed in a special mailing container, to a central laboratory, where the smears are read and the results returned to the factory. At our larger factories, where laboratories are maintained, the smears are read in the laboratories, and a few check smears are forwarded to the city laboratory, in order that the work done by the local Breed operator may be checked, which insures accuracy. A blank is used to report the bacterial findings. The dairies are listed according to number, and the class into which the milk is placed is indicated by “G” for good, “F” for fair, and “P" for poor. The dairies marked “poor” are the only ones with the actual count given. A copy of the report is sent to each factory. The laboratory makes the readings and the bureau of dairy development investigates the dairies marked“ poor."

A special form is used by the dairy inspector on which to report his findings regarding the cause for the high bacterial count. This same form is also used to follow up all milk rejected for any cause. In case milk is rejected, the receiving inspector fills out this report in duplicate, showing the dairyman's name, the number of cans returned, and the cause for the rejection. One copy is placed on file and the dairy inspector receives the other. He, in turn, visits the dairy and makes a report on the conditions found. Where this form is used for checking high bacterial counts, the dairyman's name appears together with the date of the bacterial report. The dairy inspector visits the farm and reports the cause for the high count. To render this system valuable, these high count dairies, or dairies from which milk has been rejected, should be visited as soon as possible after the report has been received. The next bacterial count taken determines whether our inspector has been successful in his efforts. In this way we are able to follow the activities of the dairy inspector. At the same time, all questionable milk is checked up, demonstrating to the dairyman that we are interested in his product, and wish to help him identify and overcome his difficulty. The result is that the quality is improved and the quantity of milk rejected is reduced to a minimum.

In case a dairyman continues to produce milk containing an excessively high bacterial content, it is necessary at times to take a sample of his milk every day until the cause is found and corrected. In exceptional cases, it is necessary to do this in order to convince a dairyman that the laboratory can determine his methods of caring for the milk and the utensils on the farm by the bacterial count. This is especially true where a milking machine is used, as the majority of dairymen who use these devices simply rinse them with cold water instead of thoroughly cleansing them after each milking.

A milk of poor quality results.

It has been found that high bacterial counts develop in the udders of cows with more frequency than is generally believed. In order to overcome this, it has become a general practice on the part of our dairy inspectors to use garget cups. Our veterinarians, when making physical examinations, use these cups to detect diseased udders.

A garget cup consists of two parts with a fine wire-mesh strainer between. Almost without exception where garget is present the first few streams of milk will show few clots of thick milk when milked into one of these garget cups. A few streams of milk from each quarter are milked upon this strainer; any cows showing any thick milk are located and the milk eliminated until the cows recover or are disposed of, as the case may demand. At times this procedure is not sufficient. Samples are then taken of the milk of each cow in the dairy, and the laboratory makes an analysis in order to locate any trouble. This is especially necessary when no apparent cause can be found for a high bacterial count, or where the Breed smears continually contain evidence of inflammation or infection, indicated by long chains of streptococci or leucocytes. The laboratory's findings are generally conclusive, and with the elimination of the milk from two to three cows, the trouble ceases.

The intelligent use of the sediment test has been of benefit in eliminating visible sediment from the milk received at the station. The cotton containing the sediment can be shown to the dairyman and it is something he can see and understand. The correction, however, is not in better straining, but in finding and removing the cause.

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The clipping and grooming of cows, wiping the udders and flanks with a clean, damp cloth, the use of a small-mouth milk pail, the draining of yards, and the racking of cans and utensils away from dusty highways, are all factors in obtaining better sediment tests. In a great many cases there does not seem to be much connection between sediment and high bacterial counts, although there is none of us who cares to use milk containing very much visible sediment.

The effectiveness of the dairy control work is measured by the quality of the finished product. At times losses occur in manufactured goods that are traceable directly to the raw product. Everything else being equal, the better the raw product the better will be the manufactured article. In our city supply of fluid milk, however, we have a very accurate record of the number of cans of sour milk and cream received. In comparing the year 1919, when the Breed control was established in our factories, with the year 1922, the results are interesting. We find during 1922, 95 per cent less sour milk, 87 per cent less sour cream, 97 per cent less sour plain condensed milk, and 73 per cent less bitter cream than in 1919. Undoubtedly these results are not entirely due to the dairy control, but this organization is certainly a vital factor. Price conditions are another very important consideration in building up a dairy field. When prices are good much can be accomplished, but when the reverse is true the work of dairy development is slower, and more difficulty is experienced in obtaining improvements.

To summarize: The means employed within the industry to improve the quality of the milk render necessary the development of an organization to carry out this work. To obtain the greatest efficiency the veterinarians, laboratory workers, dairy and receiving inspectors all should work together. Any one part of this organization is not sufficient by itself. The veterinarian has charge of the inspection work, and makes a physical examination of the cattle, eliminating any cows whose milk would be a menace to the supply. The laboratory determines the quality of the milk and furnishes the field men with information as to the dairymen who are producing a poor quality. The field inspectors visit the farms showing the low-grade milk, and through their efforts the equipment and methods are improved.

Some of our milk is bought and a premium paid for a low bacterial content to improve the quality. This method has worked out very satisfactorily, as has been evidenced by an increased number of dairymen who receive premiums, and an increased consumption. In our other supplies, where no premium is paid for a low bacterial count, the Breed method is used in determining the quality with excellent results. In tracing high bacterial counts, especially during the cold weather, we have found the cause in the udders of cows more frequently than is generally believed. The garget cup and the laboratory are very useful in locating these cases. The sediment tester has been helpful in eliminating sediment, although sediment does not necessarily mean a high bacterial content. An enormous reduction in the number of cans of unsalable products received in our New York City fluid milk market is shown by comparing the years 1919 with 1922, since the present method of dairy control has been in effect.

The development of successful dairy control has not been spontaneous, but represents years of experience. Although it has fluctuated from time to time, because of upheavals in the milk industry, the underlying principles have been correct. In years past stress was placed on the sanitary conditions and the building up of dairy fields. During the past few years this part has not been lost sight of, and the work has been augmented by laboratory controls which have been instrumental in showing the quality of the milk as received.

Clean milk produced by clean healthy cows, which has good food value, which has been properly refrigerated, and which has a low bacterial content, fulfills our requirements as to quality. Our ideal has perhaps never been reached, but we are closer to it to-day than ever before.

Mr. M. A. O'CALLAGHAN (dairy expert of the commonwealth, Melbourne, Australia). In dealing with the bacterial count your paper did not state whether or not there was a classification. That is one question. Second, how long after the milk is drawn from the cows are the smears made?

Doctor PEARCE. Milk is delivered once a day and consists of the morning's and night's milk. A sample is taken from an individual can of well-stirred milk from each dairyman's delivery. These samples are placed in ice water and refrigerated until the smears are made. The smears are made as soon as all samples are collected, which is generally in the afternoon.

Mr. 0. W. STRODTHOFF (creamery manager, Los Angeles, Calif.). Without the use of an aerator, how long does it take to cool to the center of the can?

Doctor PEARCE. In a series of tests conducted a few years ago it took from 30 to 40 minutes under ideal conditions.

Mr. STRODTHOFF. What objection do you have to the use of an aerator?

Dr. PEARCE. All dairymen have not sufficient hot water or steam to sterilize an aerator. If this utensil is not properly sterilized it does more harm than good.

Chairman WELD. The next paper is by Mr. R. W. Balderston, secretary of the Philadelphia Interstate Dairy Council, and the subject is “Motion pictures'and dairy education."

MOTION PICTURES AND DAIRY EDUCATION.

ROBERT W. BALDERSTON, secretary, Philadelphia Interstate Dairy Council, Phila

delphia, Pa.

There are about 15,000 theaters and 256,000 schools in the United States, yet about 16,000,000 persons see the movies daily, while the school attendance is only about 10,000,000. Considering education in the broad sense, that of informing and influencing public thought, the moving picture is more widely used and is a more effective agency of education to-day than is the school.

John James Tigert, now United States Commissioner of Education, has said: "A picture is a universal film which everybody understands, whatever his language may be. I believe that in Americanization, one of the greatest educational problems we have, the motion picture is going to be one of the most useful agencies. Take a man who was born in some other country, with different ideals from ours. You can teach him history out of a book, but still he will not understand America; but show him the great West, show him Jamestown, Gettysburg, Independence Hall, and tell him their stories, and he will begin to understand."

Colonel Owsley, late commander of the American Legion, in describing the systematic use of motion pictures as a means of educating our men in better citizenship, said that he could interest more than 50 per cent of his men with moving pictures. When he was asked his opinion as to the power of motion pictures to mold public opinion, he said: “I think it is far-reaching and tremendous. I know of no one other force in America at this time that has so great a power to influence public opinion. I base this statement upon first-hand observation, and upon information furnished me after a careful investigation of every city in the Nation, before we went into the film business. I became convinced that the American Legion could reach more people through the movies than through any other agency, and we have spent sums of money on motion pictures which otherwise we would have spent through our speakers' bureau.”

Thos. A. Edison, in testifying, confessed that when motion pictures were perfected, he was indifferent to the amusement possibilities of the movies. What interested him were the educational possibilities, and he devoted himself to this branch of the subject, while others developed the amusement side. He then tried to interest the school boards in moving pictures, but the big boards of education were indifferent to the idea, and the inventor says that the interests publishing books antagonized it.

The motion picture is successfully employed in dairy education in a number of ways. Several agencies are producing good films. Their distribution is very wide, although somewhat unorganized and disjointed.

The United States Department of Agriculture has a complete motion-picture bureau in its Division of Publications. It has recently completed an especially devised building, devoted to the production and distribution of motion pictures. This distribution is general through the agricultural extension service of the several States. A large number of its films are devoted to dairy topics. Many State colleges and State libraries have educational film departments, and in some States they have produced dairy films of educational value. The breed associations and other dairy organizations, and the feed and machinery companies have been active in this work.

The National Dairy Council is now regularly producing films on a wide range of dairy themes, and these are systematically distributed by district councils, as well as by the National Dairy Council headquarters. These dairy films have been shown to widely different groups of persons, as follows:

(1) Dairy farmers at country meetings see films on such subjects as better feeding, better breeding, clean milk production, cow-testing associations, and cooperative marketing.

(2) Manufacturers are shown better methods.

(3) College and high-school students are helped in the discussion of every important dairy question.

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