are not available. Refrigeration and cleanliness are also often not of the best, while frequently there is an inordinate amount of dust in the atmosphere, which readily gains access to open cans. The clerks are untrained in the principles relating to the care of milk, and occasionally the living apartments and the grocery are in close connection. All of these conditions greatly favor the entrance of bacteria to the supply and may render it unsafe for consumption.

The care of milk in the home. The care of milk in the home is not the least important of the measures for disease prevention. The container should be removed to the refrigerator as soon after it is received as possible and not be permitted to stand in the sun or even remain at room temperature. The small, insulated boxes which have recently come on the market for the reception of the bottle when delivered serve a useful purpose. Refrigeration at the home is fully as necessary as at other places, and in order to insure a pure supply ice must be used. The temperature of the refrigerator ought not to be above 50° F. All surfaces should be maintained sweet and clean, inasmuch as a dirty and foul refrigerator may be responsible for bacterial contamination.

When received, the milk should preferably be retained in the bottle, but if this is impossible a clean receptacle, kept constantly covered, should be provided. Before the contents of the bottle are removed the lip should be carefully wiped off and if dirt and moisture are present on the cap their entrance to the flowing stream should be prevented. The mixture of a milk with that of a previous day's supply facilitates bacterial growth and is to be avoided. Bottles should not be employed for other purposes than as milk containers. Upon the occurrence of any contagious disease in the house, they should be returned to the dealer only with the knowledge and consent of the board of health.

Inspection of dairies.-In order that the measures previously outlined may be enforced, the majority of progressive communities have established what is known as dairy inspection, a procedure usually carried out by the health department. The sole object of dairy inspection is to make milk safe and thus to insure community protection against disease. To be effective, control must be exercised not only at the dairy but along the entire route from the farm to the consumer. The licensing of milk dealers is dependent upon this inspection, although too frequently licenses are granted without adequate examination of the dairy or knowledge of the character of the milk.

The ideal dairy inspection is begun in the laboratory. The bacterial count of each individual supply indicates whether the milk has been carefully produced. In case the milk is found to be satisfactory, no further action is usually deemed necessary and the dairy

man, after being made acquainted with the fact that he is producing a good quality of milk, is allowed to continue with the methods which he has adopted. In case the milk is found to be bad, the producer is informed to that effect and an inspection of the dairy made to determine the cause. In many instances it is found that the farmer is ignorant of the methods of producing a pure and safe milk supply, or he may be simply careless. In either case effort is made to see that he adheres to the principles which have been enumerated and which are in the main simple and inexpensive and within the reach of all. If the dealer is unwilling to correct his methods and continues to distribute a milk which is considered dangerous for consumption, his license is revoked.

Whatever the system of dairy inspection, only the most important principles should be dwelt upon. The fact that the farmer does not have a cement floor to his stable or 4 square feet of window glass per cow should not be held against him so long as he is producing clean milk. Contrariwise, if his neighbor across the way has erected a stable, with an automatic system of ventilation, yet continues to employ milkers who habitually dip their fingers in the milk or who use unsterilized strainers, there is reason enough for disapproval. From this no one should conclude that cement floors or a stable properly illuminated are not desirable; these are matters which every farmer should see the advantages of and make arrangements for at the earliest possible date. At the same time there is not the slightest necessity for delaying the production of clean milk pending the installation of equipment of this character. Clean milk can and should be produced in the average stable. In a similar manner while no one recommends a dirty barnyard and everyone trusts that the day will come when all barnyards will be clean, we should in the meantime not neglect to urge the production of milk free from the danger of conveying disease, a matter at least not entirely dependent upon such esthetic problems as the cleanliness of the cow. or stable.

Supplementing the inspection system certain cities have established what is called the score-card system. The score card has two objects. One is to facilitate the orderly and systematic inspection of the dairy by the health official, the other to afford a concise written record of the conditions found. Dairies are marked on the basis of 100, each item, such as the healthfulness and condition of the stock, the proper care and chilling of the milk, being given so many credits, not all of the items having the same relative value.

In dairies which approach the ideal the total score may reach close to the 100 mark, while in those where sanitary precautions are not observed the score may fall below 40 or even 20. Records are maintained in the health department of the ratings as given from time to

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theless the cases of scurvy in infants which can be traced to the use of boiled milk are extremely rare. Even when fully developed the disease is strikingly curable and it is altogether preventable by the addition of a little orange juice to the diet, so that it would seem to have but little weight against the more widespread adoption of boiled milk. Inasmuch as boiled milk decomposes more rapidly than raw milk the milk should be boiled only in the home and not allowed to stand for more than a day or two before use.

Boiled milk is more constipating than raw milk and is therefore of considerable value in the treatment of diarrhea of both infants and adults. It is also more easily digested, the curds formed being smaller and softer than those of raw milk, so that it has certain advantages in the feeding of infants. For these reasons boiled milk is coming into much more general use. The single great advantage obtained from the use of boiled milk is, however, absolute freedom from the danger of contracting communicable disease. In milk which has been boiled for five minutes all organisms of a disease-producing character are killed and the supply is no longer capable of conveying the many infections which are transmitted by this substance. For these reasons boiling is to be recommended for all supplies which are suspicious as to quality and whenever there is an undue prevalence of any of the diseases mentioned. If this is done the danger of contracting disease through the use of contaminated milk altogether

ceases.

Summary.

Milk is a chemical product composed of water, fats, proteins, sugar, and various ferments and salts. The adulterations to which it is subjected detract from the food value, but are not apt to be injurious to health, while the impurities which gain entrance accidentally are of far greater consequence. Milk harbors bacteria of many varieties and favors their growth and development. If these organisms are of the disease-producing kind serious epidemics may result, and milk has come to be regarded as a frequent cause of typhoid fever, tuberculosis, the summer diarrhea of infants, and numerous other conditions. Organisms which may bring about the development of disease may be derived either from animals or from man, the latter source perhaps being the more common. In order to prevent the contamination of milk every possible avenue of infection from the farm to the consumer must be controlled. Inspection of dairies is a proper and necessary measure, but the protection it affords against the dissemination of disease is entirely insufficient. For this reason pasteurization or boiling are to be recommended.

time and in certain cities they are published, so that it is possible for every purchaser of milk to ascertain the sanitary status of the dairy from which he is receiving his supply. Ordinarily dairies which maintain an average rating of 80 or more may be considered good, those between 60 and 80 fair, while those which continually fall below 60 belong to a class in which the rules governing the production of safe milk are not observed. These figures are naturally somewhat dependent upon the strictness with which the scoring is done and the particular system followed. It is again to be remembered that a high score card rating does not necessarily mean a high quality of milk, an assumption far too common.

However thorough the inspection of dairies may be and regardless of the degree of care exercised, it should be realized that absolute protection against disease is not afforded by the measures outlined and that further means of safeguarding the purity of milk supplies are necessary. This may be accomplished by either of two methods.

Pasteurization.-The word "pasteurization" is a rather formidable name for a somewhat simple process. The majority of persons upon first hearing the term conceive of an operation incapable of being performed by the average individual. Quite the opposite is true. Pasteurization, provided the proper apparatus is at hand, is no more difficult of accomplishment than many of the processes of cooking performed by the average housewife.

The purpose of pasteurization is to kill the harmful bacteria which milk contains. It has been found that when milk is heated to a temperature of 145° F. and sustained at that point for 30 minutes the disease-causing organisms are killed. If the milk is then immediately chilled and further contamination is prevented it can no longer be considered dangerous to health. Milk which has been adequately pasteurized is therefore to be regarded as the safest milk which one can consume.

Milk may be pasteurized either at the distributing station or in the home, the ideal method being pasteurization in the final container. A number of American cities now require that all milk shall be pasteurized, so that large plants where the process is performed are common. There are a number of pasteurizers on the market for home use, but these are not essential. The milk bottles may be placed in the inner portion of an ordinary double boiler, the cold water of the smaller receptacle being on the level with the milk in the bottles. The boiler is then placed on the stove and heated until the water in the inner dish reaches a temperature of 145° F., as determined by the thermometer, where it is maintained for 30 minutes. The bottles are then removed and cooled in running water, being kept sealed until the milk is ready to serve.