No accepted or acceptable explanation of the phenomenon has yet been put forward. It has been suggested by the various authors and particularly by Fridericia et al. (1927) that bacterial synthesis of vitamin B in the intestine of the rat may be the explanation of the condition. Schieblich & Rodenkirchen (1929) have described a “vibrio-like” organism which they claim to be responsible for refection, but this finding has so far not been confirmed. In a recent dissertation on refection Nathan (1935) believes that the explanation is coupled with the nature of the starch in the diet rather than with an infection with a specific type of organism.

In our study of the relation of carcinogenicity to the physical characteristics of mineral oils we have dealt almost entirely with density, refractive index and viscosity.

1. One hundred and seventeen rats have been examined, and thirty-two or 27·3% were found to harbour virulent Leptospira.

2. The correlation of carrier conditions with the presence of immune bodies in the serum showed:

(a) Leptospira-positive, sero-reaction negative, four or 3·4%.

(b) Leptospira-positive, sero-reaction positive, twenty-eight or 23·8%.

(c) Leptospira-negative, sero-reaction positive, twenty-one or 17·9%.

(d) Leptospira negative, sero-reaction negative, sixty-four or 54·7%.

3. The titres of the immune bodies in their sera have been determined. A positive reaction in the lower dilutions of the serum does not necessarily indicate that the rat is a carrier of virulent Leptospira.

4. There is evidence to show that there is a greater incidence of carriers amongst fully grown animals than in the young rodents.

5. Rodents which have been killed prior to examination in the laboratory are unsuitable for the determination of the presence of Leptospira.

A study of the biological characters of 1636 cultures of coliform bacteria, isolated from milk and bovine faeces, shows that the coliform group consists of a large number of different types. These types are so closely interlinked in characters and in relations to environment as to justify their inclusion in one genus. Nevertheless, to facilitate the identification of types, the group may be subdivided into subgroups, the Voges-Proskauer, Koser, inositol and indole reactions being reliable and outstanding criteria for this purpose. These characters show almost perfect correlations with various other characters. Thus Voges-Proskauer-negative types have a low CO2 to H2 ratio and are methyl-red-positive; Voges-Proskauer-positive types have a high CO2 to H2 ratio, are methyl-red-negative and Koser-positive. Koser-negative types are not highly resistant to brilliant green, are non-capsulated, do not form thick mucoid colonies and are Voges-Proskauer-negative, inositol-negative and indole-positive. Koser-positive types are highly resistant to brilliant green, and with the exception of group 2 and certain members of group 3, are frequently encapsulated and form thick, mucoid colonies. Non-inositol-fermenters are as a rule motile and adonitol-negative. Inositol-fermenters are Koser-positive, adonitol-positive, sucrose-positive and raffinose-positive; are frequently encapsulated and form thick, mucoid colonies; and as a rule are non-motile. Indole-negative types are Koser-positive, while indole-positive types are generally Koser-positive or negative according to whether the inositol reactions are positive or negative.

1. Four mouse lines have been tested for “H” and “O” antibody production following inoculation with Salmonella typhi murium and S. enteritidis; two of these lines had been selected for resistance and susceptibility but not inbred; two, D and E, had been brother-sister inbred for over thirty generations but not selectively as far as resistance is concerned.

2. After immunization with S. typhi murium:

(a) Female mice, in all four lines, tend to give higher “H” and “O” titres than do males, a positive correlation between ability to produce antibody and resistance to infection being thus established.

(b) Interline differences exist for both these antibodies. Those concerned with “H” antibody may be correlated with resistance. In the case of “O” antibody, no correlation is suggested.

3. After immunization with S. enteritidis:

There appears to be no correlation sexually or interlineally between resistance and antibody production. That genetic differences exist, in respect of this organism also, is shown by the fact that the pure lines, D and E, give a better antibody response than the selected lines A and B. When tested for immunizability by subsequent infection with S. enteritidis no useful information could be obtained with strain A or B owing to their great internal variation. Strains D and E both showed a gain in expectation of life following immunization. The more resistant strain D showed a significantly greater gain than did E, the strain with a lower natural resistance.

4. The titres of normal “O” enteritidis-antibody found in the four lines indicates that there may be a negative correlation between the titre of these antibodies and resistance to infection with S. enteritidis.

5. The significance of the above findings is discussed and it is stressed that a significant correlation between resistance and antibody formation does not imply that the two phenomena are causally related.

6. It is pointed out that strains that have been inbred even without selection react far more homogeneously in the infection experiments here described than do strains that have been selected but not intensively inbred.

Nuttall was born in San Francisco, California, on 5 July 1862; the second son of Robert Kennedy Nuttall, M.D. (Aberdeen) and his wife, Magdalena, daughter of John Parrott of San Francisco. The Nuttalls were descended from an old Lancashire family, which settled in Ireland in 1707, many of its members serving as officers in the British Army. His father went to Australia, but migrated to San Francisco in 1850 and practised there till 1865. In that year the family came to Europe and remained there till 1876, the children being educated in England, France, Germany and Switzerland. Consequently, Nuttall spoke several languages, a fact which assisted him enormously in his future work and travels.

1. Two herds of cows were divided into two groups for winter feeding. One group was given the usual ration of hay, roots and “concentrates”, the other was fed on a similar diet in which part of the hay and concentrates was replaced by artificially dried grass.

2. The carotene content of the butterfat in the control group fell steadily from 0·8 mg. per 100 g. of fat to about 0·2 mg. between October and March. That of the group to which dried grass was given did not fall below 0·5 mg. per 100 g. of fat.

3. The milks from the two groups were employed in a nutritional investigation on the boys of two institutions. During a “fore-period” from July until the end of September, the boys received the ordinary milk of the herd as part of their diet. They were then divided into two groups which, during the experimental period from October until March received the “winter” or the dried grass “summer” milk respectively. Then followed an “after-period” during which all the boys received the mixed milk of the herds, then out at pasture. The composition of the basal diet of the boys at these institutions was known. Boys attending an elementary school in the vicinity of one institution were also investigated in a similar experiment but no details of their home diet were obtained.

4. Excluding children whose records were incomplete there were 159 in the group on “winter” milk, and 163 in that receiving “summer” milk.

5. Periodically records of height, weight, and chest measurement were made. All the boys were under medical supervision.

6. Statistical examination of the results fails to show that the artificially produced “summer” milk exerted a beneficial effect detectable by the improvement in growth or general condition of health.

7. The most probable explanation is that the basal diets of the two institutions were already adequate in respect to carotene and vitamin A.

8. The variations exhibited by the records of the groups provide another example of the very great difficulty of eliminating or adequately controlling sources of error in a big-scale nutrition experiment of this type.

1. The description of a strain which behaves as a pure Vi variant of S. typhi is given. Complete absence of H antigen from it is demonstrated. The non-interference in its Vi agglutinating activity by the very small amount of O antigen contained in it is shown. This strain has been designated “Vi 1”.

2. With the help of this strain, the practical applicability of Vi agglutination as a reliable method for the routine serological diagnosis of typhoid infection and for the detection of typhoid carrier condition, in preference to O and H types of agglutination, is stressed.

In an article (Scholtens, 1937) published elsewhere, I have shown that the external smooth properties of typhoid bacilli (stability in physiological salt solution and colony form) depend on the body antigens, not only on the O antigen but also on the Vi antigen.

In previous reports (Watson 1937 a, b) one of us has described a series of experiments in which various diets were tested in regard to their effect on the growth, fertility, survival and resistance of mice. It was found that, when part of the oatmeal in a particular diet was replaced by dried skimmed milk, the does were more fertile, and the young mice gained weight more rapidly and showed a lower mortality during the first 8 weeks of life. Mice bred and reared on the latter diet were found to show a significantly increased resistance to per os infection with living cultures of Bact. typhi-murium, and to the intraperitoneal injection of a toxic fraction derived from that organism. The results obtained in a few tests suggested that these mice were also more resistant to the intraperitoneal injection of living Bact. typhi-murium; but the differences observed were smaller, and of doubtful significance. In the present paper we record the effect of these two diets on the epidemic spread of mouse-typhoid.

Studies on the phenol coefficient after the cover-slip method were made on some disinfectants with the addition of different amounts of various organic materials. The results show that the phenol coefficient varies with the nature and amount of the different organic substances added to the disinfectant in question.

Ice-Cream has occasionally been proved to be the carrier of disease, and therefore a study of the ingredients used, the processes of manufacture and the bacterial content of the final product is an important branch of modern hygiene.

The purpose of these papers was:

(i) To ascertain the standardized death-rates for tuberculosis among the urban Chinese of Hong Kong.

(ii) To review the more important articles dealing with tuberculosis among the chinese.

(iii) To compare the data obtained in (ii) with those found in this survey of urban Chinese in Hong Kong.

Antigenic substances have recently been extracted in soluble form from many bacteria, and the work of Boivin & Mesrobeanu (1934), Raistrick & Topley (1934) and Topley et al. (1937) has shown that polysaccharides in combination with other non-protein substances extracted from certain Gram-negative bacilli stimulate an effective immunity in mice and specific antibody formation in rabbits. The antigenicity of similar extracts of pneumococci has not been so readily demonstrated. Berkefeld filtrates of pneumococci lysed by bile or by alternate freezing and thawing were found to be non-antigenic in rabbits (Avery & Morgan, 1925; Avery & Neill, 1925), although it was possible to immunize mice effectively with bacteria-free solutions obtained from cultures of pneumococci (Perlzweig & Steffen, 1923; Perlzweig & Keefer, 1925; Meyer, 1927). The essential antigen for the production of immunity in mice has been shown to be the type-specific polysaccharide which is effective only in small doses, usually between 0.01 and 0.00001 mg. (Schiemann & Caspar, 1927; Schiemann, 1929; Enders, 1930; Wadsworth & Brown, 1931; Avery & Goebel, 1933). The type-specific polysaccharide has, however, been found to be without antigenic activity in rabbits (Avery & Goebel, 1933; Downie, 1937).

1. Adequacy and balance in expenditure on the various items of food in the diet has been compared to the standard B.M.A. (1933) diet for a child aged 8–10 in eighty out of ninety-eight families with children attending four rural schools in Sussex.

2. The proportion that these items bear to the standard declines as the income is lower and the family larger. With the exception of bread, butter and cheese there is, in fact, a marked deterioration in the diet as the family grows, particularly in the lower groups. Bread, although declining, remains above the standard, with a few isolated exceptions, in all groups, and the proportion of cheese, although only about 60% of the amount recommended in the standard diet, remains roughly constant; butter and margarine fall below the standard only in the largest families. In contrast meat, eggs, fish, and milk, are reduced to considerably less than 50% of the standard in the larger families.

3. The balance of the diet is less defective but it is, nevertheless, profoundly influenced by growth of the family, especially where the income is small. The most marked alteration is the steadily increasing proportion of bread both as the income is lower and the family larger. In the largest families in all groups bread constitutes in the neighbourhood of one-third of the total expenditure. The tendency produced by reduction of income and increase of family to lessen the proportion of first-class protein in the diet (mainly by lessening the consumption of meat, eggs, and fish) is combated to some extent by an increasing provision of cheese, a more economical protein.

1. The effect of heroin, morphine, Dilaudid, Dicodid and Eukodol upon the human alimentary tract are described from observations involving the use of the barium meal and X-ray methods.

2. The effects of Dilaudid closely resemble those of morphine. Dilaudid produces a condition of increased tone in the pyloric and ileo-colic sphincters resulting in delayed emptying of the stomach contents into the duodenum and a delayed passage of the intestinal contents into the caecum.

3. Dicodid has a much weaker action upon the pyloric and ileo-colic sphincters than either morphine, heroin, Dilaudid or Eukodol. It causes only a negligible delay in the passage of food up to the 3 hr. stage, it being normal at the 6 hr. stage owing to a hastening of the motility rate.

4. Eukodol has an action resembling that of morphine and is described.

5. All these drugs possess well-marked analgesic properties.

6. No gross rectal symptoms were observed in any of the subjects under observation.

1. The weekly budgets of eighty out of ninety-nine families in four rural schools (containing 165 school children) and ninety-seven out of 200 families in one urban school (containing 183 school children) have been analysed.

2. Evidence is given that housewives, despite varying social status, spend between 9 and 11s. per man per week on food when the income is sufficient to allow this.

3. The lowest level of sufficiency in diet according to the instincts of the housewife is seen to correspond, at prices ruling in this district in the winter of 1936–7, with the cost of the diet of the British Medical Association Nutrition Report (1933) (7s. 8¾d.). This has been called standard A and compared with standard B costing 5s. 10¾d. which contains 1000 cal. and 13 g. of first-class protein a day less. Standard B is probably the lowest standard of diet which any authority would be prepared to recommend.

4. In the school in a prosperous urban district, in working class families (income not exceeding £4) where the children were fully embarked on the school period (i.e. the eldest child over 7 years but no child yet earning more than 10s. weekly), and which contained more than one child, 60% of children fell below standard A and 47·6% below standard B.

5. In the rural schools taking all the children, 72·2% were below standard A; where there was an income below 55s., 78% fell below standard A; below 40s. 85%; and below 35s. 91·7%. The figures below standard B were 40·6, 52·4, 60, and 75% respectively.

6. Both in urban and rural families, with the exception of high income groups (e.g. farmers), increase in the size of the family steadily lowers the allowance of food per unit. In medium wage earners the allowance of 9–11s. per unit per week when the family is small, is reduced to about 3s. when the family grows to a large size and before the first children begin to earn.

7. Most significant is the decline in the provision of first-class protein foods both in town and country in proportion as the family grows. Evidence is given that this contrasts markedly with the recognized needs of growth in childhood, and it is clear that in both town and country the large family in low wage groups produces a condition of extreme protein deficiency. Accepting 2s. per unit per week as a conservative estimate of the minimum expenditure upon first-class proteins, 13·2% of the school children in the urban school and 32·7% in the rural schools were subsisting on amounts suggesting protein starvation.

The object of this paper is to describe the immunizing procedures that have proved to be the most suitable up to the present time for preparing a potent serum from the horse for the treatment of typhoid fever. The principles on which the methods are based have their origin in the studies of Felix and his collaborators on the antigenic structure of Salmonella typhi. The technical details that follow will, we hope, assist those who are interested in the preparation of the serum as a therapeutic agent to obtain products which maintain a consistently high level of potency. This objective is not readily attained, but is of paramount importance, because the clinical use of products that fall below the permissible limits of potency would tend to bring discredit upon the serum as a specific remedy owing to insufficient dosage. The adoption of standards of potency that are prescribed by an official authority is an obvious desideratum and would guard against this risk, but in the meantime we shall be pleased to help by providing the requisite cultures and serological reagents.

We know, since the time of Pasteur, that repeated passage of rabies street virus from rabbit to rabbit after intracerebral inoculation, leads to a modification of its effect and the appearance of mutative characters. This takes place at a variable period of time depending upon the strain employed. The irreversibility and the permanence of these characters has led to the name of “fixed virus” once the street virus has become adapted for the rabbit.