In devoting to the foundation of a memorial lectureship a portion of Dr. Maudsley's bequest, the learned Society which I have this afternoon the honour to address made an indulgent concession to the laity in prescribing that the lecture to be delivered should in alternate years be of a scientific and of a popular character. This year it is the turn of the popular lecturer—a rôle which I have assumed with some trepidation. The distinction drawn is an ominous one. It seems to suggest that to be scientific you must be unpopular, and to be popular you must be unscientific. But is there necessarily so absolute a dividing line between the two domains? I hazard the view that it is possible to be at once both popular and scientific. No doubt there is still a tendency in learned circles to deride what is known as popular science, but that is an inheritance from the days of the cheap and inaccurate manuals which used to be written by imperfectly informed persons, pretentiously professing to enlighten the masses on the truths of science. Nowadays, science has become more condescending, indeed almost affable, to democracy. The approach has come from both sides, for democracy is now better educated, and science is now more expert in the art of exposition. The advent of the internal combustion engine, of wireless telegraphy and of many other practical applications of science to daily life has created a new and widespread interest and aptitude on the part of the general public in the acquisition of accurate scientific knowledge, particularly among the younger generation. At the same time the physicist, the chemist and the biologist have found it possible and worth while to impart much of their learning to wider audiences. Science is daily entering more and more into the lives of the people, with the consequence that its social, economic and political implications are being more and more realized by its professors. The President of the Royal Society has reminded us that we live in an age when the advance and development of scientific knowledge are continually creating new social and economic problems of the utmost importance, and has emphasized the necessity of bridging the gap between the scientist and the layman by every possible means. The British Science Guild, now doing such excellent work, was founded some thirty years ago by Sir Norman Lockyer for the express purpose of promoting the application of scientific method and results to social problems and public affairs. The market-place can doubtless never supersede the laboratory, but the scientist no longer disdains to take his wares to market.

Melancholia is one of the great words of psychiatry. Suffering many mutations, at one time the tenacious guardian of outworn schemes or errant theories; presently misused, cavilled at, dispossessed, it has endured into our own times, a part of medical terminology no less than of common speech. It would seem profitable to consider the history of this word, and of the states of fear and distress with which it has from the beginning been associated.

The starting-point for a physiological understanding of the above-mentioned diseases consisted in some new laboratory facts obtained in the course of the study of conditioned reflexes in dogs.

Pregnancy, with the associated pain and danger of labour and the Puerperium, is an ordeal for any woman, more so perhaps to-day than it has ever been, because of the wide publicity given to the toll of puerperal infection and the need for ante-natal care. An experience so intimately connected with the love-life, and with social and economic difficulties also, is often a period of acute mental stress in perfectly healthy women. Still more is it a time of psychological tension in those constitutionally unstable and liable to mental breakdown, both because they are not able to withstand the strain of mental conflict, and because they are the more likely to meet with such emotional problems on account of their temperamental unbalance.

Before proceeding with the subject of this paper, it is my very great privilege to extend to the distinguished members of the Royal Medico-Psychological Association the cordial greetings of my own Chief of Service, Dr. W. Parsons, the Commissioner of the New York State Department of Mental Hygiene, who has long held in high respect his European acquaintances in the field of psychiatry; in particular, those residing in the British Isles. For purpose of clarity it should be explained that the Department of Mental Hygiene is a branch of the State Government, and the Commissioner is charged with the execution of the laws relating to the custody, care and treatment of the insane, mental defectives and epileptics in all public and private licensed institutions.

While, during the last thirty years, great advances have been made in our knowledge of inhibition, its properties and its interactions with excitation, yet little progress has been made in elucidating the precise nature of inhibition itself. Pavlov (67), for instance, has discovered many of the principles of inhibition, its interaction with excitation, its irradiation, its extinction and so on. But all the time he is dealing with inhibition simply as a phenomenon which shows itself in the end-reaction. With regard to what is actually happening in the cortex, he admits that it is unknown. Yet the phenomenon of inhibition is one of prime importance in the organization of the central nervous system. Perhaps, at times, while watching, say, a dog chasing a ball, one is apt to forget the many reactions which are not happening in one's interest in what is happening. Yet an overdose of strychnine to the dog will soon remind one that every movement of each limb, every twitch of a muscle is surrounded, as it were, by a wall of inhibition, checking, controlling and timing so as to produce the final smooth and graceful co-ordination.

In the psychological field, the two significant streams of thought are the Pavlovian and the Freudian, the physiological approach of Leningrad and the psycho-analytic approach of Vienna. It will be suggested here that they are not divergent streams as is often thought, but convergent, and that in the impact between them lies the more immediate future of psychology.

It has generally been considered by obstetricians and psychiatrists that the insanity of pregnancy, in common with other forms of insanity associated with the reproductive function, offers a favourable prognosis from the point of view of complete mental recovery of the mother. This standard view is to be found in most text-books on midwifery and mental diseases.

In the care and treatment of mental patients there has been great progress. In our fight against the disease, the psychosis, which disorganizes the higher mental functions, we have achieved numerous therapeutic successes. I need only mention malarial therapy in dementia paralytica, salvarsan and trypar-samide for cerebral syphilis, the treatment of the digestive organs in cases of toxæmic psychoses, the removal of focal infections in numerous cases of schizophrenic derangement, the somnifaine prolonged narcosis treatment in manic-depressive psychosis, non-specific stimulation in various other psychotic conditions. The great importance of underlying somatic causes and of a rational somatic therapy are fully recognized, and it remains the principal task of the psychiatrist to search for the causes of the psychoses and for the means of combating and preventing them.

In 1920 Marinesco and Radovici (1) described a reflex contraction of the homolateral chin muscles in response to stimulation—pricking or pinching—of the thenar surface of the hand. They record a case of amyotrophic lateral sclerosis where such a stimulus evoked a slow contraction involving the triangularis and quadratus menti of the same side. In this particular case the reflex could be elicited not only from the palmar region, but also from the skin of the arms, thorax and abdomen, also by stimulation of the perinæum, effected by passing a urethral sound. The lowest threshold of reflex excitability was, however, obtained on the palm.

The periods under review were selected according to the availability of suitable material. Before the year 1907 and during the years of the Great War the number of deaths divided into suitable age-groups are not readily obtainable. The years immediately following the end of the war were considered to be unsuitable owing to the occurrence of epidemics of influenza.

The value of prolonged narcosis as a form of treatment in mental disorder has been well recognized in Switzerland, Germany, Holland and the U.S.A., but, so far, there has been little tendency to adopt the method in this country. It is true that there has been considerable diversity of opinion about its efficacy, but it must be remembered that much of the literature published reveals that there has been a general lack of uniformity as to technique, duration and drug used, apart from discrepancies in the interpretation of results. Furthermore, one of the most potent arguments against the treatment has been its dangers— a fact which has deterred many psychiatrists from giving it a trial. These dangers, however, instead of stimulating research into possible methods which might eliminate toxicity of narcosis, gave rise to a search for a Utopian narcotic, which would serve therapeutically whilst being free from toxic effects. No less than forty substances (according to Palmer and Paine (1)) have been tried, with but little result except to increase the confusion. In a previous communication by one of us (2) toxic symptoms of narcosis were discussed, and a method was described whereby these could largely be eliminated with doses of narcotic sufficient to produce prolonged, continuous sleep. In the present paper it is proposed to summarize and comment on therapeutic results in 107 mixed cases of mental disorder, in which a total number of 128 treatments were carried out. In 117 of these treatments somnifaine was used, in 9 veronal, and in 2 dial.

The use of inoculation malaria as a method of pyretotherapy still involves a relatively high figure of mortality and has other drawbacks. For example, there are the difficulties in propagating the culture, the loss of time entailed by the periods of incubation and removal of the fever, the uncertainty whether the inoculation will be successful, and the impossibility of a simultaneous administration of arsenical preparations; further, the fact that the treatment cannot be repeated satisfactorily, together with the occurrence of splenic and hepatic complications. A method of inducing pyrexia that promises freedom from these, at times, irksome conditions is therefore worthy of trial.

The following examination of the clinical features of depressive states is based on the detailed study of 61 cases examined and treated by the writer at the Maudsley Hospital, London.

Female homicides can be conveniently considered under three headings: (i) Those who kill their children, (2) those who kill adults, and (3) abortionists. The last group has not been included in the 126 cases under review, because the mental condition of the abortionists is of little interest for our present purpose. I have never known a prisoner charged with this offence raise the subject in mitigation of punishment. The 126 cases are not in any way selected, but are the total number of murder charges I have had under my care at Holloway prison during the years 1923 to 1932, excluding cases of abortion. I have selected the year 1923 because the Legislature introduced the Infanticide Act in the previous year; this Act effected certain changes in practice to which I shall refer again in some detail.

The investigations herein set forth have been chiefly confined to the mobile tissue of the body, the blood. It is manifest that in abnormal biochemical changes affecting the organism in whole or part, this medium will be the locus, where such changes might reasonably present themselves and be detected by the means at our command. The substances therefore with which I shall be dealing are all normally present in the blood to a greater or less degree, but show marked variations under the stress of a mental breakdown. In particular I shall concentrate on lecithin, one of the phospholipins, cholesterol, belonging to the sterol group, and choline, which is classed with the animal bases.

About a year ago I came to realize that my knowledge of the subject of treatment in epilepsy was far from being complete, and this paper is the outcome of efforts made to clear up some of the uncertainty which existed in my mind.

It has been stated that in schizophrenia the usual specific dynamic action (S.D.A) of foodstuffs is not shown. In order to be certain that the S.D.A. of foodstuffs is less in schizophrenics than in normal subjects, it was considered desirable to attempt a form of examination in which information would be available not only concerning the rate of absorption of the ingested material, but also concerning the excretion of products of metabolism which would be increased during and after the period in which the S.D.A. was evident. Accordingly the results dealt with in this paper are based entirely on the findings of chemical changes in the blood and urine of the subjects investigated after administration of the selected agent.

Serological tests on the blood of mental defectives have been, both here and in other countries, the subject of numerous investigations, but the cerebrospinal fluids of the entire population of a large mental defective institution have never, as far as I am aware, been systematically examined. This paper deals with the results of such an investigation in 2,000 cases of mental deficiency of both sexes, all ages and grades, patients at Caterham Mental Hospital during the last four years, and with the complications following lumbar puncture.