The experiments recorded in this paper were undertaken in order to ascertain the effects of certain dyes and allied organic compounds on three selected species of bacteria, Staphylococcus aureus, B. coli and B. pyocyaneus. These experiments show that in cultures the results are influenced by many factors, and appear to suggest that the varying results of the use of these compounds in the treatment of wounds may be ascribed to some extent to the different conditions prevailing in each case.

In order to obtain cultures of aerobic bacteria from single cells it is hardly necessary to insist that a method of isolation should be employed which can be relied on to ensure that one organism, and one only, is the starting point for inoculation of the first subculture. Unfortunately, for technical reasons which will be explained, no such method is at present available.

In a paper published in the Journal of the R.A.M.C., December 1917, it was demonstrated, that B. tetani was susceptible of classification by serological methods into at least three “Types.” Since the publication of that paper, a fourth Type has been encountered; but, so far, it has been demonstrated only in five instances—four being from cases of declared tetanus which were not, however, fatal.

The present figures show that the virus may be present in the blood as early as 18 hours and as late as 90 hours after the onset. It was not found in the blood 130 hours and 190 hours after the onset.

The virus outside the body has been found alive, if kept reasonably cool, in several instances up to 48 hours, and in one instance after 99 hours.

It is not possible from this series to draw deductions from the negative cases on this question.

Several mosquito experiments in this series have not therefore added to our previous knowledge, but the one satisfactory experiment with Culex fatigans tends to support the view we hold that this species is probably not a vector of the disease. The results previously published by us support the opinion of Bancroft (5) and show clearly that, whether or not C. fatigans may also play a part in Australia, Stegomyia fasciata is capable of spreading the infection of dengu.

(1) The antiseptic and bactericidal properties of Flavines and Brilliant Green. Extended investigations have confirmed the original values. It has been shown that the inferior potencies recorded by certain other workers depend on the use of methods unsuited for the observation of antiseptic properties, i.e. they fail to detect inhibition of bacterial activity i.e. bacteriostatic action, which is exhibited to a marked degree by flavine and brilliant green.

(2) For the therapy of a local bacterial infection, as in a wound, such bacteriostatic action is of great value. It is not essential that the chemical agent should by itself actually kill the organisms. Highly successful results can be obtained by a co-operation of the antiseptic and the tissues, so that the pathogenic action of the organisms is restrained. The flavines in virtue of their low toxicity to mammalian tissues and their high bacteriostatic power are therefore specially suited to act as local therapeutic agents. In addition, the fact that they are not neutralised by admixture with serum enables them to be applied clinically by a relatively simple method which does not necessitate frequent renewal.

(3) The “fundamental error” to which the method of testing chlorine antiseptics originally practised by Dakin, is liable, and which Dakin and Dunham have drawn attention to, has been shown not to affect our previous results with Chloramine-T. The difference between our values and the others is due to the fact that we employed 80 per cent. serum in the test.medium, which is much more active in neutralising this antiseptic than is 33 to 50 per cent. serum employed by Dakin and his co-workers.

Following the capture of Jerusalem and in the early months of 1918 Capt. C. M. Craig, R.A.M.C., obtained a culture of a proteus-like bacillus from the civil Jewish bacteriologist of that city. He was informed that this organism was being extensively used by German and Austrian bacteriologists on the Eastern front for the diagnosis of Typhus Fever. After making some preliminary observations on its agglutination by the sera of typhus patients he forwarded the culture on to this laboratory for further investigation, the preliminary account of which was published by Craig and Fairley (21 Sept., 1918, Lancet, pp. 385–6).

Two instances are described of sera showing abnormal anti-complementary power. The amount of complement fixed by the serum was in the one case about six times, in the other about four times, greater than is normal. Examination of subsequent specimens from the patients showed that this inhibitory character was transient only. No feature common to the two cases was found to which the abnormality could be attributed. Attention is drawn to the rarity of this condition, but it is of practical importance in that such sera would be regarded as giving a positive Wassermann reaction if their behaviour in the absence of antigen were not observed.

Although true meningococci are represented in serum 1, as shown by the high agglutination figure reached with serum 1 in the case of subculture 8, it appears that the antigenic value of strain 1, as represented in serum 1, finds its chief expression in “giant” forms, the morphological equivalent of films 3, 14, 17, 23, 31 A, from the subcultures which give the highest readings with serum 1 (except 8), being mainly that of “giant” forms in various stages of development. As I showed in 1916 “giant” forms may be either large, small or intermediate in size, and can at once be distinguished from true meningococci on the warm-stage by the fact that they often multiply by unequal binary fission, and by the further fact that they often undergo in addition endo-chromatinolysis, giving rise directly to meningococci which then divide in the ordinary vegetative manner. These fertile “giant” forms are readily distinguishable form forms undergoing genuine involutionary changes, both by the sterility of the latter when observed on the warm stage and by their feebly-staining properties.

1. Throughout the war the food value of the dietaries investigated with one exception showed great constancy, temporary shortage of certain commodities being compensated for by the greater use of others, especially of flour.

2. The food consumed was determined much more by the income and dietary habits of the families than by the restrictions imposed by rationing. The marked variations in the energy value of one dietary from time to time (normally a generous one) were directly caused by changes of income.

3. The children of three families were markedly below the average in height and weight. As the energy available in the food of these families only averaged 40 per cent. above their basal requirements calculated according to age and body surface, it seems probable that the interruption of growth had been caused by an insufficient supply of food.

4. A fourth family had at two periods of study an equally low intake of energy, but during the other two studies had at least 100 per cent. above the basal energy requirements. As the children were normal in development, growth was apparently unchecked by the temporary periods of food shortage.

The question of standardising bacteriological methods is at present under discussion and, although it is most undesirable that any one method should be forced on all bacteriologists, it is certainly resonable that any method which has given excellent results in the hands of a number of independent workers should have a strong recommendation.

1. Investigation by American bactriologists have shown that the lactose-fermenting (gas-producing) bacilli can be divided into two main types distinguishabel by the methyl-red and Voges-Proskauer reactions.

2. The methyl-red- Voges-Proskauer + type are shwon to be rare in human and animal faeces, more common in surface water, milk and sewage, and the predominant type in soil and grain, and to be more resistant than the methyl-red + Voges-Proskauer-type.

3. Investigations by the author of this paper confirm their findings as regards human and animal faeces, water, milk and grain. An investigation of the types present in soil is being undertaken and it is hoped to publish an account of this later. Already the “M.R.—” type has been found to predominate in four out of six samples of soil.

4. In the present investigation organisms of the “M.R.—” type were found in 66 samples of water out of a total of 200 containing lactose-fermenters, and in 41 samples containing this type no evidence of recent contamination could be adduced by the search for organisms of the “M.R.+” type ofStreptococci. Judgment of the water was therfore liable to modifiction in 20% of these samples by the recognition of this type.

5. Twenty-nineout of the 66 samples containing organisms of the “M.R.—” type were from sources of good repute, most of them from public supplies.

6. The presence of lactose-formenters of the “M.R.—”“V.P.+” type must be regarded with considerable less disfavour than the presence of “M.R.+” “V.P.—” organisms, and the application of tests for the recognition of these types is impotant. It is suggested that these tests should be included in all routine examinations of water and food products.

In conclusion I have pleasue in acknowledging my indebtedness to Dr. W.G.Savage for calling my attention to the reserches of American bacteriologist and for many valuable suggestions he has made in connection with this work.

The Japanese investigators (Inada and Ido) who discovered the Spirochaeta icterohaemorrhagiae, the cause of infectious jaundice, showed that the serum of patients who had recovered from the disease contained immune substances which were capable of destroying the spirochaetes in the blood and tissues of an experimentally infected guinea-pig. They found that if the serum were injected into the guinea-pig prior to the appearance of icterus the disease was inhibited in all cases. The same result was obtained with the serum of immunised goats.

Experiments I–VIII.

I shows that under the conditions shown the plates were covered with innumerable colonies 7 feet above ground level to ground level. The beds and trestles were used to keep the hut always uniform.

II shows that 8 feet above ground, i.e. on top of the crossbeams, the same conditions obtain.

III, IV, V, and VI show that the same condition exists in the area between the beds or trestles. The beds make no difference, better or worse.

VII shows practically the same condition high up on the beam between the beds. The inverted plates naturally show less colonies, as the organisms mostly fall on to the plates.

VIII confirms the above.

There is only one conclusion to draw from these experiments, and that is that practically speaking there is no difference in the number of organisms on the ground floor and 8 feet above it, in the ordinary men’s sleeping huts, Barrack Design 230/14.

The research on which this paper is based, was carried out between September 1916, and April 1917, while the writer was in charge of the Carrier Depot Hospital, Nairobi, British East Africa.

1. The disease is an acute encephalo-myelitis produced by a virus akin to, but not identical with, that of the Heine-Medin disease.

2. The disease was readily communicated, with fatal results, to monkeys (Macacus rhesus) by intracerebral inoculation of a suitably-prepared emulsion of nervous substance (brain, cerebellum, pons, medulla and spinal cord) from the human subject dead from “X disease.” Moreover, the virus was found to breed true in a succession of thirteen monkey (Macacus rhesus) generations.

3. The disease was not communicated to Macacus cynomolgus (several trials).

4. The disease was communicated by the above-mentioned method from monkey to sheep (10 times), from sheep back to monkey and on again from monkey to monkey.

5. A certain number of sheep, perhaps 50 per cent., were found wholly insusceptible to the disease; others suffered lightly and recovered.

6. The disease was communicated, with fatal results, by the same method, from monkey to horse (1 case) and to calf (1 case). Two calves suffered lightly after intracerebral inoculation of the usual virus-containing material taken from monkey and horse respectively.

7. The virus appears to be held back completely, or to a great degree, by the pores of a Berkefeld filter.

8. Storage of the virus-containing material in diluted glycerine, under cool conditions, for longer than a few days, reduced or annulled its nocive properties.

9. Drying of the virus-containing material in Petri dishes, in an incubator, probably destroys its activity.

10. In the case of the sheep, there was failure to induce the disease by swabbing the nostrils with virus-containing emulsion.

11. There is some evidence that in the case of the sheep and the calf a previous inoculation with the virus confers immunity.

12. One experiment suggested that artificial immunity might be induced in the monkey by inoculation of virus treated with serum from an “X disease” sheep.

13. Intracerebral inoculation of three dogs, one kitten, two rabbits and one hen failed to produce any signs of the disease; and similar inoculations of two guinea-pigs gave doubtful results.

14. Treatment of the virus-containing emulsion with (a) normal human serum, (b) serum from recovered human cases of “acute poliomyelitis” and (c) serum from “X disease” sheep prolonged the incubation period of the disease in the monkey but did not destroy the virus.

15. Normal sheep serum and serum from “X disease” sheep did not neutralise the virus in its operation on other sheep.

16. Two experiments suggested that the virus was no longer present in the monkey on the eighth or tenth day of illness.

17. Two experiments towards the end of the investigation suggested a waning in strength of the virus.

18. Intraperitoneal and intrasciatic inoculations of virus-containing material, also intracerebral inoculations of cerebro-spinal fluid, of a filtrate of faeces, of a “Noguchi culture,” of an emulsion of fowl ticks, of naso-pharyngeal swabs from human cases and contacts, and inoculations into veins, all failed.

It is a widely accepted belief amongst medical men, particularly those who are Medical Officers of Health, that cats may suffer from diphtheria and convey it to human cases and that they are a not uncommon source of infection. It is of considerable practical importance to determine to what extent this belief is based upon reliable scientific data or whether it is another of those opinions, still far too prevalent, which arise from the acceptance of insufficiently tested and incorrectly interpreted observations.

As there appears to be a considerable amount of uncertainty (as evidenced by recent writings on this subject) regarding the biological relationships and the etiological significance of the so-called “atypical B. dysenteriae,” this short communication is intended as a brief résumé of conclusions arrived at in the course of an extended investigation of dysentery bacilli in Egypt during 1916 and 1917. It is to be noted that the results recorded here were obtained from the examination of cases of dysentery observed in the earliest stages and frequently followed into convalescence. Such experience has shown that conclusions derived solely from an investigation of the later stages of the disease, e.g. convalescents examined after arrival from over-seas in the United Kingdom, throw little light on the problem of the bacterial etiology of the disease as a whole. In a paper by Thomson and Mackie (1917) on the clinical and laboratory study of dysentery in Egypt a number of atypical dysentery strains were described, but at the time this communication was submitted for publication my observations were not sufficiently complete to make any general statements regarding organisms of this type and no attempt was made to classify them.

In December 1917, Lieut.-Col. MacGilchrist of the Indian Medical Service published a paper on the necrosis produced by intra-muscular injections of strong solutions of quinine salts. It might be an advantage to quote the first few lines of this communication: “Advocates of intra-muscular injections of strong solutions of quinine salts for the treatment of malaria seldom omit to state that no local ill-effects are produced”. He records a case of tissue necrosis following on the intra-muscular injection of eleven grains of quinine bi-hydrochloride in thirty-four minims of water. Death supervened thirteen hours later. MacGilchrist especially noted, owing to rapid tissue necrosis, that the track of the needle remained patent. He regards as an established fact that most of the quinine injected is precipitated and probably chemically combined with serum proteins in the necrosed tissues and for this reason intramuscular injections of concentrated solutions of quinine salts are not to be recommended for cases of emergency. Very dilute solutions of quinine salts are, in his opinion, rapidly and completely absorbed whether employed subcutaneously or by the intra-muscular route. If the views which MacGilchrist puts forward in this and other communications are to be accepted without reserve then intra-muscular injections of strong solutions of quinine should no longer be employed. It was for this reason that Major-General Sir M. P. C. Holt, K.C.B., K.C.M.G., D.M.S., B.S.F., asked me to carry out an experimental enquiry on animals as to the effects produced by intra-muscular injections of strong solutions of quinine.