All seven series give answers in the same sense, and we may conclude that we have definite experimental evidence that fatness increases the susceptibility to death from caisson disease. The regularity of the results in the guinea-pig experiments suggests that fatness is here the predominant influence in individual susceptibility. The difference in weight between the “survived” and ‘died” is not always in the same sense, and is in no case very large. The weight factor may therefore be relatively excluded in considering these results : indirectly it is of influence in that rats, like men, tend to become fatter as they grow older. Our results show pretty clearly that females are fatter than males, and, in the guinea-pig series, much more susceptible. Femality, like age, is not a quality which can per se have any influence on susceptibility. The increased susceptibility of females is probably simply due to their increased fatness, which tends to further increase during pregnancy. With regard to symptoms other than death our evidence is very meagre. Some symptoms, e.g. bends, may be presumed to be independent of fatness.

The following general statements are applicable to the 50 cases of cerebrospinal fever which have been under notice here.

The total volume of serum given did not affect the frequency of abnormal reactions.

The total number of injections of serum, in certain cases, may have been a factor in inducding abnormal reactions.

The interval of time between the injections concerned was the primary influence in determining abnormal reactions.

It was not apparent that a preceding normal reaction predisposed to a subsequent abnormal reaction.

It was not apparent that a large administration of serum within the latent period predisposed to a subsequent abnormal reaction.

In 1901 Miss Anderson (H.M. Principal Lady Inspector of Factories) and Dr Legge (H.M. Medical Inspector Factories) were instructed by H.M. Chief Inspector of Factories to investigate the conditions of labour in the Tinning of metals and metal articles with a view to the preparation of regulations for the conduct of this industry. Difficulties having arisen in assigning a cause for the plumbism undoubtedly existing among workers, and preparation of regulations appearing impossible without some knowledge of the source of illness, the writer was instructed to assist them experimentally in determining the causes.

We intend to give in this paper a short account of (1) the laws concerning the supply of drinking water to ships in some of the chief civilised countries of the world; (2) the results of bacteriological examination of the water on steamships; (3) the chief deficiencies in supply and storage which have come under our notice, and (4) the reforms which we consider urgently necessary.

Hitherto all efforts to set up immunity against vaccinia in animals have been restricted to the vaccination of animals in the customary manner, or to the injection of vaccine lymph into them.

1. Temperature influences the rate at which glycerinated lymph deteriorates in accordance with the law of Arrhenius, expressing the effect of temperature upon chemical action; the rate of deterioration increasing three times per 10° rise in temperature.

2. Dry powdered calf vaccine in sealed glass capillary tubes still gave rise to typical vesicles after exposure to a temperature of 100°C. for from 5 to 10 minutes.

3. The vaccine virus can withstand positive osmosis for 24 hours or more, and negative osmosis for 8 weeks or more, at room temperature.

4. It appears doubtful whether the vaccine virus will pass through a Berkefeld V filter even when a stored vaccine emulsion is used for filtration. If any virus does pass through it only does so exceptionally and in small quantities.

5. When a glycerinated vaccine emulsion is filtered, white flocculi frequently form in the filtrate. These are at first minute, but subsequently adhere and form a macroscopic sediment. This sediment, when inoculated on calves, does not cause vesiculation.

Microscopically these flocculi, in hanging drop preparations, resemble the vaccine bodies described by one or more observers.

In a recent paper by Miss Chick on “The Laws of Disinfection”, it was pointed out that disinfection of bacteria is strictly analogous to a chemical reaction in which individual bacteria play the part of molecules. Thus, if n be the number of bacteria present at any time t during dis-infection, , where K is a constant. Also, if K1, K2 are these constants for two different temperatures is also constant, i.e. Arrhenius' formula for the temperature coefficient of chemical reactions holds good in the case of bacteria as well. In addition to this, it was found that the relation between the concentration of the disinfectant and the time of disinfection (that is, the time required to reduce the original number of bacteria by a given percentage) might abe approximately expressed by the empirical law

where C is the concentration at time t.

Whilst the studies of A. C. Houston and MacConkey have extended our knowledge of the characters of the bacilli found in faeces, and those of Dudgeon and Sargent have done the same with regard to colon bacilli met with in cases of appendicitis, the fermentative activities of pathogenic colon bacilli occurring in urine have not been investigated to any great extent.