use may cause the loss of invaluable time at the only stage when cancer is believed to be amenable to radical treatment, namely, the very earliest stage. Another cancer "cure" was found to consist essentially of potassium iodid, an agent which is frequently employed in the treatment of syphilitic affections. It often forms a part of "cures" of this kind, its use being really directed to the relief of syphilitic troubles which are erroneously believed to be of a cancerous nature. The Post Office Department has issued nearly a dozen fraud orders in this class of cases and as a result the mail-order cancer cure business has practically been suppressed in this country.

Two consumption "cures were investigated. Both were found to contain ordinary medicinal agents which might perhaps have a temporary and palliative effect in relieving the distressing symptoms of the disease, but which can not in any proper sense be considered as cures for consumption. Millions of dollars are spent annually to retard the progress of pulmonary tuberculosis, but it is well known that there is at present no specific for its treatment. Anyone engaged in exploiting a so-called consumption "cure" is simply trafficking in the life and health of the people, since the time lost in such a way may result in the death of the victim by delaying the use of proper hygienic

measures.

In addition, there were investigated disguised treatments for the prevention of conception and for the production of abortion, for the restoration of hearing, and for the cure of rheumatism, and other diseases.

STUDIES OF FOODS AND FOOD MATERIALS.

SPECIAL INVESTIGATIONS OF THE DIVISION OF FOODS.

FRUIT PRODUCTS.

The economic studies relating to fruit products have been continued in cooperation with the pomologist in charge of field investigations of the Bureau of Plant Industry. In connection with the study of the utilization of surplus fruit the yield of juices made in different ways from various fruits has been studied on a scale sufficiently large to be easily extended to commercial proportions. Special attention has been given to the causes of the disappearance of flavor in the juices of citrus fruits after sterilization. The preparation of dried sugared pineapples has been studied on a scale large enough to secure data applicable on a commercial basis. The investigation of the ripening of persimmons without softening has been continued. and has shown that this can be best effected by confining the fruit in a closed space in an atmosphere of carbon dioxid. Thus far the experiments have been conducted on a laboratory scale, but field work is planned for the coming season as a result of which it is believed that definite directions can be given for commercial processing by the

grower.

A study of the respiration of fruits as an index of their physiological activities has been continued and extended to cover the effect of temperature on the vital processes. It has been found that various. fruits differ widely in their rate of respiration, but that they are similarly affected by changes in temperature. The respiration in all

cases was increased about 2.5 times for each rise in temperature of 10° C. In cooperation with the Office of Nutrition Investigations, Office of Experiment Stations, the bureau is now studying the heat evolved by the banana during ripening in the respiration calorimeter.

THE MANUFACTURE OF CITRUS BY-PRODUCTS.

Owing to the difference in economic conditions the methods employed for the manufacture of citrus by-products in southern Europe are not applicable in the United States. A laboratory study has been made with a view to increasing the use of mechanical devices and otherwise lessening the cost of production, and has reached the stage where it seems advisable to conduct the work on a commercial scale. It is proposed, therefore, at the beginning of the next packing season, to equip a small experimental plant for the study of the economic manufacture from waste citrus fruits of citric acid, citrus oils, juices, and several preserved products.

ESSENTIAL OILS USED FOR FLAVORING FOOD PRODUCTS.

An investigation of citrus-fruit oils extending over several years has been completed during the past year, and a report upon the subject is in preparation. A study was also made of the manufacture, composition, and methods of analysis of the oils of wintergreen and birch and of methyl salicylate. It is important to know the distinguishing characteristics of these products, as the last two are frequently substituted for the wintergreen. Other essential oils, such as oil of sassafras and spearmint oil, were also studied.

FIELD EXPERIMENTS IN THE MANUFACTURE OF CIDER VINEGAR.

In order to determine the changes taking place during the conversion of cider into vinegar under commercial conditions, a field laboratory was established at a factory in Benton Harbor, Mich., and also one in Albion, N. Y. The plan of the work was to make analyses of the cider used as a vinegar stock and then collect samples of this after it had passed through generators and been converted into vinegar, in order to determine the exact changes which took place during this acetification.

This experiment was carried on during a period of several months, as it was found to take some time for the effect of a change in composition of the cider to show itself in the finished vinegar. Some very valuable information was obtained, showing that in the acetification of the cider by the generator process practically the only change is the conversion of the alcohol into acetic acid. It was also shown that the generator vinegar is very much more uniform in composition than vinegars made by the old-fashioned barrel process, during which they are subjected to varying conditions, and that certain relations exist between the ingredients of the generator vinegar which are valuable in detecting adulteration of the commercial product. The glycerin present in the fermented cider was not affected by the conversion into vinegar, and a very valuable factor was thus obtained for the detection of adulteration, which has been used in a number of cases to great advantage, proving conclusively the dilution of cider vinegar with the distilled product.

THE INFLUENCE OF TIN RECEPTACLES ON THEIR CONTENTS.

This study has been continued during the past year. A set of samples of 11 varieties of foods packed in lacquered containers of heavy and light coating were examined for the second time after the interval of a year, to note the increase of tin content on storage. Samples of 22 additional varieties of foods were examined 6 months after canning, in order to determine the amount of tin contained in the foods at the earliest date at which they are likely to reach the consumer. Additional samples of these goods are retained for future examination. The results thus far obtained indicate that some of the acid fruits when packed in plain tin contain from 200 to 250 mg of tin per kilogram of material, exclusive of juice, at the earliest date on which they are likely to reach the consumer, and that this amount is greatly increased after a year's additional storage. The amount of tin dissolved by the food is greatly decreased by the use of lacquered tin.

Special attention has been given to the question as related to a number of foods which are practically free from acid, but which are known to attack tin to a considerable extent, such as canned shrimp, pumpkin, and string beans. Since this action was most pronounced with shrimps, they were first studied, and it appeared that the action in such cases is due to the presence of volatile alkalies, inasmuch as mono-methyl-amin was found in considerable quantities in canned shrimps and amins and amino acids are present in the foods mentioned.

EDIBLE OILS.

In collaboration with the Bureau of Plant Industry, progress has been made in the clarification of peanut oil, and a study has been inaugurated of the chemical composition of various soft-shelled pecans and of the oil contained by them, with a view to determining whether the composition would shed any light on the distinguishing features of various varieties.

WORMY AND DECOMPOSED FOODS.

Certain classes of dried fruits in a wormy and partially decayed condition continue to be placed on the market. This results from several causes-sometimes from curing by imperfect methods and in insanitary surroundings, and sometimes from careless storage, the products being exposed unduly to the attacks of insects. In ripe olives decay has sometimes resulted from the practice of discarding the brine in which they were originally packed, for the purpose of saving freight. In such cases, especially when shipments are exposed to unusual delay, the goods reached this country in a condition that did not warrant their use as food. The risk involved in this method of shipment has been pointed out.

It has frequently happened also that a considerable portion of the ripe olives shipped in bulk were contaminated by worms. Figs and marrons, imported into the country to a considerable extent in the fall, were frequently found to be wormy and sometimes moldy and decayed. The efforts of the department in this direction have

resulted in a great improvement in such imported products, and it is believed that the foundation has been laid for far greater improvement during the coming season.

An extensive study has been made of the manufacture of foods from waste, trimmings, and especially from material undergoing decomposition and of the elaboration of methods by which the use of such material could be detected by the examination of the finished article. The first attention was given to the study of tomato ketchup, with the result that it is now possible to distinguish in a general way the product made from sound, ripe, and properly cleaned tomatoes from those in the preparation of which unfit material was employed. During the last year the bureau has come in contact with a large number of manufacturers of ketchup, and it is believed that great progress has been made in the elimination of the use of decomposed material in the manufacture of this product. A beginning has been made in the application of the same and similar methods to the inspection of manufactured fruit products such as jellies, jams, and marmalades. The question is still being studied both in the laboratory and in the factory.

CAUSES OF SPOILAGE OF CANNED FOODS, KETCHUPS, ETC.

Work was continued during the past season on food preservation and the methods of preventing spoilage. The study of the cause of reddening of dried cod and other salt fish was continued, especially at Gloucester, Mass. Many suggestions were made for improving the sanitary condition of the water supply and of the fish factories, which, if carried out, it is believed will lessen infection and the resultant spoilage.

During the manufacturing season experiments were continued at Lafayette, Ind., in the making of tomato ketchup, using pulps of varying quality and cleanliness and in different states of spoilage. The completed product gives evidence of the character of material used, and the method of manufacture can not completely disguise the facts when the product is subjected to microscopic and chemical tests. The three most important factors in producing a clean ketchup are the selection of the fruit, thorough washing, and rapid handling of the product in the course of manufacture. Studies were also continued on the different factors which tend to preserve the ketchup. It was found that no one of the spices nor all the spices in combination when used only in the quantities necessary for flavoring had any preservative effect. The keeping quality depends principally on quality of the raw product, cleanliness of manufacture, the concentration of the tomato pulp with the sugar and vinegar, and upon sterilization.

The work upon canned goods consisted largely in a study of the proper quantity of material to use in the can, and the degree of temperature and length of time that should be given in processing in order to get the best result in the finished product. There is opportunity for improving the general quality of canned goods, but the specific directions can not be given until the results of several seasons' work have been accumulated.

FOOD COLORS.

Two extensive studies on coal-tar colors have been brought to completion during the past year under the direction of B. C. Hesse, of New York, a color expert appointed for the purpose of making these investigations. The food-inspection laboratories at Washington, at New York, and at Seattle have also done a great deal of work along this line. The first investigation included the original work done in the bureau and also a comprehensive survey of the literature with special reference to the harmfulness of coal-tar colors and their physiological effects. These data, on which the selection of the seven permitted colors was based, are in the hands of the printer. The second study consisted in the investigation of methods for determining the chemical identity of coal-tar dyes used in food products, as a result of which 134 different chemical individuals have been grouped in 10 analytical tables. Of these only 19 are paired, leaving 115 dyes which can be conclusively identified by these tables without known specimens. The dyes of each of these pairs can be thus distinguished from every other pair and from each of the other 115 dyes, but the pairs can be distinguished from each other only by having known specimens of at least one member of the pair. In no case is one of the permitted dyes of Food Inspection Decision No. 76 paired with another dye. The tables include all but three of the dyes said to be used in food products, and these appear to be now obsolete; they also include all dyes that have been examined physiologically and which are not obsolete or impracticable for use in foods. These data are now in process of compilation.

The investigation of the character of artificial colors used in various food products has been continued and admission into the United States has been denied to foods colored with unpermitted dyes. Considerable attention has also been given to the natural coloring matter in foods, especially in flours in connection with the bleaching process, and the application of the spectroscope to the general problem. A study has also been begun of the coloring matter of the common foods which have a characteristic color with a view to establishing another means for the detection of the substitution of one food for another.

MANUFACTURE AND COMPOSITION OF EGG NOODLES.

This product is assuming considerable importance, and it has become necessary to be able to determine from the examination of the finished article the proportion of eggs used in its preparation. With this in view, a representative of the bureau visited a large factory and with the assistance of trained workers manufactured under commercial cónditions egg noodles made with varying amounts of egg and from various classes of eggs. The analyses of these preparations have afforded valuable data for judging accurately of the quality of commercial products.

COMPOSITION OF BEER MADE FROM VARIOUS MATERIALS.

In collaboration with a local brewery, samples have been taken of various beers at different stages of their manufacture, and the data obtained from their examination are believed to be of value in the