observations would indicate that the sensation of hunger is caused by contractions of the empty stomach.

Contributions to the physiology of the stomach.-III, The contractions of the empty stomach inhibited reflexly from the mouth, A. J. CARLSON (Amer. Jour. Physiol., 31 (1913), No. 4, pp. 212-222, figs. 6). It was observed that the movements of mastication with the mouth empty produced no inhibition of the stomach contraction, and that the movements of swallowing gave only very slight inhibition.

Stimulation of the gustatory nerves of the mouth, however, by holding salt, sugar, acids, and alkalis in the mouth, by chewing an indifferent substance (e. g., paraffin), or by tasting or chewing palatable foods, produced inhibition of the stomach contractions directly proportional to the strength of the stimuli and inversely proportional to the degree of the stomach activity. It was further found that "the inhibition of the stomach activity and the cessation of the hunger pains run parallel." The author states that while the detailed mechanism of the inhibitions of the contractions of the empty stomach from the mouth remains to be worked out by further experiments, he believes them to be primary or fundamental reflexes and not dependent on the memory processes.

Concerning the resorption and retention of calcium and phosphorus by the intestine, F. ZUCKMAYER (Pflüger's Arch. Physiol., 148 (1912), No. 4–5, pp. 225, 256, fig. 1).-The author's investigations lead to the conclusion that colloidal potassium phosphates probably play a part in the resorption of the calcium supplied in the food.

The creatin content of muscle under normal conditions-its relation to the urinary creatinin, V. C. MYERS and M. S. FINE (Jour. Biol. Chem., 14 (1913), No. 1, pp. 9-26).—The percentage of creatin in the muscles of laboratory animals and a few specimens of human muscle was found to be not only constant for a given animal, but the figures appeared to be distinctive in each case. The creatin elimination appeared to bear a constant relation to the percentage of muscle creatin. A constant relation was also found to exist between the daily elimination of creatinin and the total amount of creatin in the body, animals with a high daily elimination having a proportionately higher content of body creatin. The figures for urinary creatin followed the body weight in each case in the experiment. The authors believe that the constancy in the content of muscle creatin offers a satisfactory explanation of the constant daily elimination of creatinin which they and other workers have found.

A respiration apparatus, H. MURSCHHAUSER (Biochem. Ztschr., 42 (1912), No. 4, pp. 262-280, pl. 1, figs. 2).—A full description is given of an open air circuit apparatus for measuring the products of respiration of small animals.

The subject is placed in a small glass chamber which is kept at any desired temperature by being immersed in a water bath, the temperature of which is controlled by a thermostat. Provision is also made for the maintenance of the incoming air at any desired temperature and for the removal of carbon dioxid and water from it. Apparatus for complete analysis of the expired air forms a part of the apparatus.

Animal calorimetry.-I, A small respiration calorimeter, H. B. WILLIAMS (Jour. Biol. Chem., 12 (1912), No. 3, pp. 317-347, pls. 3, figs. 4).-This article describes a small respiration calorimeter of the same general type as that developed by Atwater and Rosa and designed especially for work with infants and small animals.

Special glass bottles are used for containing the sulphuric acid for the absorption of water vapor, and an automatic device for the admission of oxygen is employed. The temperature of the water entering the calorimeter is kept constant in two ways; it is fed to the heater at a constant temperature by first

passing through a coil immersed in a tank of water provided with a Gouy temperature regulator, and fluctuations in the heating current are prevented by means of a special "mercury-chloroform" regulator which is described fully. The author states that in "actual experimental work changes of more than 0.01-0.02° practically never occur except when it becomes necessary to change the temperature voluntarily."

Results and descriptions of control experiments proving the accuracy of the apparatus are also given.

Animal calorimetry.-II, Metabolism of the dog following the ingestion of meat in large quantity, H. B. WILLIAMS, J. A. RICHE, and G. LUSK (Jour. Biol. Chem., 12 (1912), No. 3, pp. 349–376, tables 3).—A dog which produced 22.3 calories during an hour previous to food ingestion was given 1,200 gm. of meat. The heat production rose to 36 calories in the second hour and to 42 in the third and was maintained above 40 calories per hour through the tenth hour. In the fourteenth hour it had fallen to 37 calories. It remained at 30 calories up to the eighteenth hour and fell rapidly to 25 calories in the twentyfirst hour. The ingestion of 700 gm. of meat by the same dog caused an increase of metabolism which was less than that caused by 1,200 gm., but in proportion to the quantity ingested.

"The increased metabolism was proportional to the nitrogen elimination. except in the second and third hours. In the second hour the metabolism rose almost to its maximum although the urinary nitrogen reached only a third of its maximum. Since the nonprotein respiratory quotient for this period was often above 90, it appears that carbohydrate and not additional protein was oxidized during this hour. On this is based the argument that the incoming amino acids. in proportion to their mass action, stimulate the protoplasm to higher oxidation."

The calculated heat production did not always agree with that actually measured by the calorimeter during the second and third hours. This "is largely due to the fact that the rectal temperature of the dog does not give a measure of the temperature increase of the whole dog" since the skin temperature was found to rise higher than the rectal temperature after the ingestion of the food.

The authors conclude that the carbon derived from protein metabolism was retained in the organism as dextrose, since calculations based on this assumption showed that the actual quantity of oxygen absorbed agreed closely with that required, which would not have been the case if it had been stored as fat. The dextrose retained in relation to nitrogen eliminated was 1.2: 1.

Intestinal work was believed to have little to do with the increased heat production, since a high metabolism was maintained after the work of the intestinal canal must have been largely completed.

Animal calorimetry.-III, Metabolism after the ingestion of dextrose and fat, including the behavior of water, urea, and sodium chlorid solutions, G. LUSK and J. A. RICHE (Jour. Biol. Chem., 13 (1912), No. 1, pp. 27–47, fig. 1).— The ingestion of from 50 to 100 gm. of dextrose gave rise to an increase of 20 per cent in the metabolism of energy of a dog during the first 4 or 5 hours after ingestion.

This increase was not believed to be due to the stimulation of the cells to greater action by the osmotic changes set up by the sugar entering the blood stream, since the ingestion of water and solutions of salt and urea, which were isotonic with the solutions of dextrose given, had no effect on the metabolism. but rather to the presence of an amount of readily oxidizable carbohydrate in the blood greater than is noted when there is no absorption of carbohydrate

from the intestine. The ingestion of olive oil, which, like dextrose, is readily absorbed, caused an increase of metabolism, probably for the same reason. Animal calorimetry.-IV, Observations on the absorption of dextrose and the effect it has upon the composition of the blood, GERTRUDE FISHER and MARY B. WISHART (Jour. Biol. Chem., 13 (1912), No. 1, pp. 49–61, fig. 1).—A rapid absorption of the dextrose occurred during the first hour after ingestion and the sugar content of the blood rose above the normal.

At the end of the second hour about three-fourths of the ingested sugar was absorbed, little being retained as glycogen by the liver, and the sugar in the blood had returned to normal. This condition lasted through the third hour, and during the fourth hour the absorption was completed, the volume of the urine increased suddenly, and the increased metabolism ended.

Animal calorimetry.-V, The influence of the ingestion of amino acids upon metabolism, G. LUSK and J. A. RICHE (Jour. Biol. Chem., 13 (1912), No. 2, pp. 155-183, table 1).-Results of experiments are given from which the authors conclude "that the increase in metabolism after the ingestion of meat is due to the mass action of amino acids acting as stimuli upon the cellular protoplasm." The observations upon which they base their conclusion are as follows:

The increase of heat production in dogs during the 2 or 3 hours following the ingestion of meat was much greater than could be derived from the protein metabolism shown to have taken place during that period.

Following the ingestion of glycocoll, the heat production rose to its maximum in the second hour when very little glycocoll had been destroyed. That the increased heat production was not due to the process of deaminization and urea production was shown by the fact that when glutamic acid, which is freely absorbed and deaminized, was ingested, no increase in heat production took place. It appeared from this that "the increase in metabolism during the second hour after giving glycocoll must be due to direct stimulus upon the cells." The action of alanin was similar to that of glycocoll but it was not so powerful a stimulant. Leucin and tyrosin also showed a slight stimulative action.

A mixture of 5.5 gm. each of glycocoll, alanin, glutamic acid, leucin, and tyrosin showed a more rapid metabolism of the constituents than when they were given alone. The effect on metabolism was as pronounced as that produced by 25 gm. of glycocoll and greater than that of 100 gm. of meat containing the same quantity of nitrogen.

The influence of glycocoll and alanin is not due to the fact that they produce nausea or to movements of the intestines, since urea solutions, which produce nausea, and saline cathartics do not influence metabolism.

Glycocoll and alanin do not act like sugar, into which they are both completely convertible. Instead of acting through the metabolism products which they form, which have practically no effect on the heat production, they act as stimuli on the protoplasm with which they come in contact.

Animal calorimetry.-VI. The influence of mixtures of foodstuffs upon metabolism, G. LUSK and J. A. RICHE (Jour. Biol. Chem., 13 (1912), No. 2, pp. 185-207, tables 2).-On a standard diet of 100 gm. of meat, 100 gm. of biscuit meal, and 20 gm. of lard, upon which a dog was maintained for 6 months, the average hourly heat production was 23.3 calories during the first 4 hours after ingestion. On reducing the meat to 33 gm. the heat production fell to 22.8 calories, while on replacing 67 gm. of the meat with 20 gm. of glutamic acid it fell to 22.7 calories per hour.

On a diet of 50 gm. of biscuit meal the heat production was 19.1 calories per hour, which was unchanged by the addition of 10 gm. of lard. The further

addition of 33 gm. of meat to this mixture was followed by a metabolism of 20.6 calories per hour. As 100 gm. of meat alone was found to give an apparent metabolism of 20.2 calories per hour, it appeared possible that the amino acids in the meat and biscuit meal might determine the height of metabolism when the above diet was given.

When the mixture of 50 gm. of biscuit meal, 33 gm. of meat, and 10 gm. of lard was given with 20 gm. of glutamic acid and with 20 gm. of alanin, the heat production remained unchanged at 20.1 calories per hour. Although 20 gm. of alanin given alone was found to increase the metabolism from 16.2 calories to 19.2 calories per hour, it was without effect when given with a diet which, of itself, produced a higher metabolism. When the above mixed diet was given with 20 gm. of glycocoll, the metabolism rose to 22.8 calories per hour, the same level found to be produced by 25 gm. of glycocoll when given alone. "It appears, therefore, that in this case the metabolism rose to the height which glycocoll alone would have induced."

The authors believe that these results give a more exact conception of metabolism. A large oxidation of fat and carbohydrate is believed to take place when these substances are furnished to the cells in larger amounts during the absorption of food, but a moderate addition of fat to the diet may not increase a metabolism which is already raised to a higher level by the inges tion of carbohydrate. "Addition of meat or of amino acids to a mixed diet does not increase the metabolism of fat and carbohydrate unless the stimulus of the amino acids would alone effect this result.

"One may conclude that there are the following forms of metabolism in the quiet or sleeping dog excluded from thermal influences: (1) A basal metab olism when the cells are nourished by a blood stream which does not receive food from the intestinal tract but the composition of which is regulated by the organs of the body; (2) a metabolism due to plethora, induced by an increased quantity of carbohydrate of fat metabolites in the blood on account of absorp tion from the intestine; and (3) a metabolism due to the stimulus of amino acids." The last two can not be added and no summation of effect occurs when the two influences act simultaneously. "In other words, the level of cellular oxidation induced by plethora is not further heightened by the stimulus of amino acids, unless the latter alone would accomplish such increase in activity."

Metabolism of seurvy in an adult, L. BAUMANN and C P. HOWARD (Trans. Assoc. Amer. Physicians, 27 (1912), pp. 514–533, fig. 1).—In this case, the addition of orange juice to the diet of the patient was followed by an increase in the amount of nitrogen and mineral constituents retained in the body, as shown by metabolism experiments.

New experiments on the importance of training in the production of muscular work, H. PEDER (Skand. Arch. Physiol., 27 (1912), No. 4-6, pp. 314340, figs. 8).-From experimental data recorded, the conclusion is reached that the ability to perform muscular work can be materially increased in a short time by constant training, that the muscular power decreases markedly when training is discontinued, that performing severe work will keep muscular efficiency at a high level for a long time, and that training causes marked increase in endurance.

ANIMAL PRODUCTION.

Cold-storage business features, G. K. HOLMES (U. S. Dept. Agr., Bur. Statis. Bul. 93, pp. 86, figs. 3).—A statistical study of the business features of cold storage, a preliminary account of which has been previously noted (E. S. R., 27, p. 164).

The information was obtained from statements of warehousemen regarding receipts of fresh beef, mutton, pork, dressed poultry, butter, and eggs for each month during a period of 2 years. The records began in March, 1909, for dressed poultry and eggs, and in May, 1909, for the other commodities, and included schedules for statements of the deliveries for each month out of storage to the end of August, 1911. There were also schedules for the storage of freshly frozen fish, but as they were incomplete no statistical study was made of them.

The relative monthly receipts are shown in the following table:

Relative monthly receipts of fresh beef, mutton, pork, butter, dressed poultry, and eggs.

1909-10 1910-11 1909-10 1910-11 1909-10 1910-11 1909-10 1910-11 1909-10 1910-11 1909-10 1910-11

It is established by this investigation that 71.2 per cent of the fresh beef received into cold storage in the year 1909-10 was delivered within 3 months, 28.8 per cent of the fresh mutton, 95.2 per cent of the fresh pork, 75.7 per cent of the dressed poultry, 40.2 per cent of the butter, and 14.3 per cent of the eggs. Within 4 months after it was received, 86 per cent of the fresh beef was delivered, 42.7 per cent of the fresh mutton, 96.5 per cent of the fresh pork, 85.3 per cent of the dressed poultry, 53.4 per cent of the butter, and 22.6 per cent of the eggs. The percentage of receipts delivered in 7 months is 99 for fresh beef, 99.3 per cent for fresh mutton, 99.9 per cent for fresh pork, 96.1 per cent for dressed poultry, 88.4 per cent for butter, and 75.8 per cent for eggs. Those in 10 months are 99.7 per cent for fresh beef, 99.5 per cent for fresh mutton, 99.9 per cent for fresh pork, 98.9 per cent for dressed poultry, 97.8 per cent for butter, and 99.9 per cent for eggs.

For the following year, 1910-11, the deliveries of 3 and 4 months were mostly considerably below those quoted for 1909-10. Comparisons could not be made for the longer periods.

The important observation to be made is that the receipts into cold storage are entirely or very nearly exhausted by the deliveries within 10 months. Very small percentages of some of the commodities were stored for a much longer time, but these are explained by warehouse men as being caused by special circumstances of an uncommercial nature.

"From the natural storage year ending August, 1910, 9.6 per cent of the receipts was carried over to the next year in the case of fresh beef; the percentage for fresh mutton for the natural storage year ending July, 1910, was