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WHEN a substance composed of microscopic particles is subjected to chemical or mechanical disintegration wherein the dimensions of the particles approach the range of 2—100μμ or if the aggregation of molecularly dispersed particles is arrested within this range, a colloidal condition is attained. In most types of emulsification encountered in lubricating practice the former of these two conditions operates and microscopic droplets of water are formed which undergo by chemical and mechanical processes a reduction in size to colloidal dimensions. For certain steam cylinder oils and soluble cutting oils the formation of stable oil‐water emulsions is desirable, but can be detrimental in the case of steam turbine lubricants where it is essential to employ an oil which shows rapid demulsification.

In the first part of this article, in our last issue, DR. BRANCKER discussed the fundamental elements of emulsification, the orientation and wetting theories and their connections with lubrication. In this part he discusses metal cleaning, solid emulsions and atomisation. The theories discussed are of primary importance in connection with spraying metal surfaces for corrosion inhibition or for lubrication. The theories of atomisation are also important in connection with lubrication by aerosols.

Originally, this article took the form of the Twenty‐first Brancker Memorial Lecture delivered to a meeting of The Institute of Transport. The author began his lecture by saying how honoured he was by the invitation to present the 1964 Brancker Memorial Lecture and that he felt especially privileged to have the opportunity of surveying a prospect which he believed would have excited Sir Sefton Brancker's most ardent enthusiasm—the prospect of reducing inter‐continental journey times‐by air to the same durations as those universally accepted for inter‐city journeys by rail and road. Previous Brancker Memorial Lectures had summarized the general development of British civil aviation from its earliest days to 1946 and had covered particular aspects of its very rapid expansion since that date. 1946 was a significant year because it marked the resurgence of commercial flying after seven years of wartime restrictions and regulation; it promised a new deal to both operators and travelling public, with the opportunity of usefully applying technical advances achieved during the war period; at the same time it threw into sharp contrast the relative design capabilities of the British and American aircraft manufacturing industries.

The aeronautical engineer is all the time struggling to improve aircraft performance. His problem is essentially the attainment of maximum economy—to get the maximum duty out of the material at his disposal. In the field of aerodynamics his progress depends upon the progress of his knowledge of the behaviour of air in a variety of circumstances. In the field of structures it depends upon the exactness of his knowledge of the distribution of stress and strain. In the field of oscillations, where the influences of aerodynamics, structures and inertia combine, he needs the support of the theory of vibration.

ON the basis of the kinetic theory, molecules in a liquid, at a given temperature, are at a certain energy level. Before the molecules can undergo a transition to a higher energy level they must acquire an activation energy designated by E. The Maxwell distribution law states that the number of molecules possessing sufficient energy for transition are in relation to the expression e‐E/RT where R is the gas particularly over extended temperature ranges, a study has been made of these deviations to ascertain whether they are anomalous or whether equation la fails to apply to such cases.

ONE of the most significant institutions of our day is the Central Library for Students. This truism—which we have frequently stressed—was emphasised by the Report of the Library which was presented at the Annual Meeting held at University College, London, on May 16th. The number of books issued, which was 52,711, does not seem large in comparison with the figures that an average‐sized municipal or county library can present; but the difference lies in the purposefulness which those figures represent. Nearly every book here recorded was one required for special work; few, if any, were for idle reading or for the occupation of undirected leisure. We note with pleasure that the outlier libraries lent 1,606 books out of 1,814 for which call was made. It seems a fair proportion. We were not clear if the balance unsupplied by them was supplied from the funds of the Central Library itself. We appreciate these outlier libraries, who are able to be such owing to grants from the Carnegie Trust, but we look more earnestly to a greater growth of the voluntary co‐operation which has found its adherents in the public libraries. There are now seven urban and two county libraries who place their stocks at the disposal of the Central Library for Students. Why not all of them? As we have said on an earlier occasion, if all adhered, the demands on any one would be small and the advantages without limit.

Increasing evidence is accumulating that biomedical and lifestyle factors account for rather small proportions of population variance in incidence of cardiovascular disease (CVD). In North America, however, the medical and public health communities – reinforced by narrow media coverage focused on biomedical and lifestyle issues – remain wedded to these models of cause and prevention. Not surprisingly, public perceptions of the causes of CVD mirror these preoccupations. A review commissioned by a community heart health network brought together the evidence of how CVD results primarily from material deprivation, excessive psychosocial stress, and the adoption of unhealthy coping behaviors. The review has served to help shift thinking about CVD prevention in Canada and the USA.

International studies indicate that offenders have higher rates of infectious diseases, chronic diseases, and physical disorders relative to the general population. Although social determinants of health have been found to affect the mental health of a population, less information is available regarding the impact of social determinants on physical health, especially among offenders. The purpose of this paper is to examine the relationship between social determinants and the physical health status of federal Canadian offenders.

The study included all men admitted to federal institutions between 1 April 2012 and 30 September 2012 (n=2,273) who consented to the intake health assessment. Logistic regression analyses were used to explore whether age group, Aboriginal ancestry, and each of the individual social determinants significantly predicted a variety of health conditions.

The majority of men reported having a physical health condition and had experienced social determinants associated with adverse health outcomes, especially men of Aboriginal ancestry. Two social determinants factors in particular were consistently related to the health of offenders, a history of childhood abuse, and the use of social assistance.

The study is limited to the use of self-report data. Additionally, the measures of social determinants of health were indicators taken from assessments that provided only rough estimates of the constructs rather than from established measures.

A better understanding of how these factors affect offenders can inform strategies to address correctional health issues and reduce the impact of chronic conditions through targeted correctional education and intervention programmes.