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TOXOPLASMOSIS IN CHILDHOOD
813 Screening of the chest showed no evidence of enlargement right ventricle, but it was felt at this time that a real danger of progressive cor pulmonale was present, although dyspnoea was not yet severe and the patient’s general health was still good. of the
Treatment with radioactive iodine seemed indicated, and Sept. 11, 1951, a dose of 20 mC was given by mouth. Of this 56% was excreted in forty-eight hours, the uptake in the chest reaching 35% in twenty-four hours. Two months later a fourth tracer dose showed a maximal uptake in the chest of 46% at twenty-four hours, and a second treatment dose was then given, this time of 102 mC. A fairly prolonged radiation sickness followed this, and the patient did not recover normal vitality for about two months. Transient lymphopenia developed but no dangerous depression of the
formance of objective tests of lung function ; and it has been confirmed by definite clearing of the X-ray shadows in the lungs. (I am indebted to Dr. G. Simon for the interpretation of these films.)
Summary
on
marrow.
A further tracer study on June 19, 1952, nine months after this last treatment, showed that the uptake by the lungs had now risen still further, reaching 56% of the dose at twentyfour hours, with no demonstrable uptake in the neck. Calculation (Oddie 1951) showed that the therapeutic doses should have provided local irradiation of about 10,000 r.e.p. throughout the lungs. It seemed that effective ablative doses of radioactive iodine would have to be prohibitively high, and X-ray therapy also, if an adequate response were to be obtained. Treatment with thyroxine was therefore started in the hope that the metastases might behave like nodular goitre and slowly regress. L-thyroxine was used because it contains less non-hormonal iodine than does the racemic form, and less than thyroid extract, and would not therefore interfere with any subsequent tracer studies. Sodium-1-thyroxine was started on July 16, 1952, in a dosage of 01 mg. daily, which was slowly increased until by Oct. 7 the patient was receiving 10 mg. daily, with the production of signs of mild toxicity. The dosage was reduced to 07 mg. daily, at which level no symptoms were produced, and the patient was then readmitted for further tracer studies. On Dec. 15, 1952, 99% of an intravenous tracer dose was excreted in forty-eight hours, without any demonstrable uptake either in the chest or in the neck. Thyroxine was then discontinued, and four weeks later, on Jan. 12, 1953, the patient was readmitted for further study. She now presented the typical appearance of hypothyroidism ; the uptake of radio-iodine in the chest reached 26% of the dose at twenty-four hours, with no demonstrable concentration elsewhere. Further Progress.-Since then she has been maintained on thyroxine, without intermission, in a dosage of 0-5 mg. daily. There has been a slow but considerable reduction in dyspnoea ; the lung-function tests have been repeated and show a rise in the maximal breathing capacity, from 47 litres a minute to 79 litres a minute, although the vital capacity has remained unaltered at 2070 c.cm. ; and there is now a slight but definite clearing of the X-ray shadows in the lungs.
Discussion Dr. I am indebted to G. J. Cunningham for his report on the histology of the local recurrence in the neck. The tumour here was well differentiated, and it is likely that the pulmonary metastases are similar to it. This is confirmed by the ability of the pulmonary metastases to pick up iodide, as the tracer studies showed ; and the patient’s euthyroid state despite total thyroidectomy was presumably attributable to their activity. The suppression of iodide uptake after treatment with thyroxine parallels that observed in healthy people both in its degree and in its duration (Greer 1951, Morgans et al. 1952). It was followed by a phase of rebound hypothyroidism, as in healthy people (Farquharson and Squires 1941). It is reasonable to suppose that the mechanism of this lies in the suppression, by the administered hormone, of the pituitary output of thyrotrophic hormone, as in healthy people, and the resultant diminution in activity of the thyroid gland. This would indicate the dependence of the pulmonary thyroid tissue on normal thyrotrophic stimulation from
the pituitary.
Regression of the metastases after treatment thyroxine was shown by clinical improvement, lessening of dyspn(Ea subjectively and a better
with with per-
A case of well-differentiated thyroid carcinoma is described in which very numerous functioning deposits in the lungs proved resistant to treatment with radioactive iodine, but now appear to have been satisfactorily suppressed as a result of prolonged treatment with
thyroxine. This patient was in the first place under the care of Mr. 1. G. Williams, and my thanks are due to him and to Dr. A. E. Jones for permission to publish her case. As an inpatient she was under the care of Prof. R. V. Christie, to whom I am grateful for permission to publish and for help with the preparation of this paper. The radio-iodine studies were undertaken by the Department of Physics, and I am indebted to Prof. J. Rotblat and to Mr. G. M. Owen for the great deal of careful work they have done. REFERENCES
Danowski, T. S., Huff, S. J., Tarail, R., Wirth, P., Peters, J. H., Mateer, F. M., Garver, K. (1952) J. clin. Endocrin. 12, 1572. Farquharson, R. F., Squires, A. H. (1941) Trans. Ass. Amer. Phycns, 56, 87. Greer, M. A. (1951) New Engl. J. Med. 244, 385. Astwood, E. B. (1953) J. clin. Endocrin. 13, 1312. Morgans, M. E., Oldham, A. K., Trotter, W. R. (1952) J. Endocrinol 8, 250. Oddie, T. H. (1951) Brit. J. Radiol. 24, 333. Perlmutter, M., Weisenfeld, S., Slater, S., Wallace, E. Z., David, M. M. (1952) J. clin. Endocrin. 12, 208. Riggs, D. S., Man, E. B., Winkler, A. W. (1945) J. clin. Invest. 24, 722. —
Preliminary
Communication
TOXOPLASMOSIS IN CHILDHOOD PATIENTS with
unexplained pyrexia
of
7-10
days
duration accompanied by generalised lymphadenopathy and sometimes by a rash and splenomégaly are commonly seen in the outpatient department of a children’s hospital. A blood-count shows a leucocytosis of 10,000-15,000 per c.mm. with an increase in the proportion of polymorph cells, a threefold or fourfold increase in the absolute eosinophil-count, and no glandular fever " cells. The Paul-Bunnell test is negative despite a reasonable clinical diagnosis of infectious mononucleosis. Throughout the world it has been found that up to 50% of apparently normal adults have a positive dye test for toxoplasmosis, while less than 10% have complement-fixing antibodies. In toxoplasmosis the complement-fixation test is believed to become positive later, and its titre to fall more quickly, than does the dye test. Although domestic animals are presumed to be the reservoir of infection, apart from congenital toxoplasmosis little is known of how or when man becomes infected with toxoplasmas or whether the initial exposure to the parasite, leading to the production of antibodies, is invariably unassociated with symptoms. The lack of explanation for the numbers of cases of children with pyrexia and lymphadenopathy, and their resemblance to known cases of acquired toxoplasmosis, "
RESULTS OF DYE TEST AND COMPLEMENT-FIXATION TEST IN 20 CASES OF CHILDREN WITH UNEXPLAINED PYREXIA AND LYMPHADENOPATHY
814 led me to wonder whether this condition might represent the first, antibody-stimulating exposure to toxoplasmas, resembling a primary tuberculous complex. INVESTIGATION
Sera from 20 children and young adults suspected on clinical grounds of having glandular fever were all found to give a negative Paul-Bunnell test. Toxoplasma dye and complement-fixation tests were made, and the findings are shown in the accompanying table. COMMENT
These results were unexpected, because of both the number of positive findings and of the high titres. It is Still difficult to know, in the absence of recognised signs of toxoplasmosis, what attention to pay to positive serological findings, but a titre of 1/8 for the complementfixation test is generally regarded as of some diagnostic significance. Of the 20 cases 6 had titres in excess of this ; while in a 7th case where the serum was anticomplementary the dye-test titre was 1/256-four times as high as that usually found in the symptomless adult. These preliminary findings are far too incomplete for any firm conclusions. A much larger series of cases of glandular enlargement must be investigated, and a long follow-up is being undertaken to observe changes in antibody titre. Also the haematological findings must be accurately correlated with the serological. But the present data do lend support to the belief that some, at least, of the cases of apparently non-specific generalised lymphadenopathy with pyrexia in children may be due to toxoplasma infection, and that the positiveserological tests so often found in the symptomless adult may be a residuum of such infection. The Hospital for Sick Children, I. A. B. CATHIE Great Ormond Street, London
M.D. Lond., M.R.C.P.
Reviews of Books Rh-Hr Blood
Types Applications in Clinical and Legal pology. ALEXANDER S. WIENER,
Medicine and AnthroM.D., F.A.C.P., senior to the office of the chief medical examiner of Stratton. 1954. New York City. New York : Grune &
serologist
Pp. 763. $11.50. An Rh-Hr Syllabus The Types and their Applications. ALEXANDER S. WIENER. New York : Grune & Stratton. 1954. Pp. 82.$3.75.
BETWEEN 1929 and 1953 Dr. Wiener and his co-workers 333 papers on the Rh-Hr blood types. The first of the two volumes reviewed here gives a, full list arranged in years. The papers have appeared not only in the United States but also in British, French, and Italian journals and some others. From these numerous and often important writings Dr. Wiener has selected 84 to represent his contribution to every aspect of the subject. As they have been reproduced from the originals by a photographic process, the book inevitably contains a mixture of sizes and shapes of type which makes for difficult reading ; sometimes the reproduction is not too clear and some of the more complex tables need a magnifying-glass. It may be useful to have this collection under one cover, but the relatively few experts directly interested in the subject are likely to have read the principal papers already and probably possess reprints. The non-expert will hardly tackle so difficult a set of papers, and in his Rh-Hr Syllabus Dr. Wiener himself has in fact provided them with a much shorter and simpler account of his work. The Syllabus is an excellent little monograph, containing all that anyone not actually pursuing research into blood-groups needs to know about the Rh-Hr blood-group system and the pathological conditions in which it is concerned. It begins with a series of definitions of fundamentals, and the next two chapters, on Rh antibodies and on the serology and genetics of
published
i
the Rh-Hr types, contain short didactic discussion, illustrated by clear diagrams. A fairly long and remark. ably informative chapter on erythroblastosis fœtalis is followed by short chapters on blood-transfusion, anthropology, and medicolegal applications. Unfortunately Dr. Wiener’s views on nomenclature introduce difficulties for many of the readers who would benefit most from his book. In this country the CDE n menclature is in everyday use; but, as is well known, Dr. Wiener regards it as misguided and misleading, and will have none of it. As things stand, the ordinary student needs the help of books that, unlike Dr. Wiener’s, make But it is a a fair job of collating the two systems. measure of his skill that he makes his subject plain despite the complexity of the notation which the devotees of the theory of multiple alleles find necessary for’the expression of their ideas.
Spot Diagnosis Volume, 1. Compiled by the Editors of Medicine Illustrated. London: Harvey & Blythe. 1954. Pp. 128. 7s. 6d. THIS is an entertaining and teasing book. The reader is invited to examine a photograph and consider some clues ; he must then make a diagnosis, and answer some questions, before turning to the right answer on the next page (rather too handy for those who readily succumb to temptation). Most of the pictures have appeared under similar examination conditions in Medicine Illtistrated. The game is both instructive and aggravating ; for the baffled diagnostician learns from his mistakes, yet complains that he would have done better, of course, in the flesh or with a coloured photograph. And he may be annoyed when a non-fluctuant swelling turns out to be a cold abscess, even though the answer generously excuses him from blame in this case. One or two of the conditions are on the rare side, but then many of the commoner diseases do not lend themselves to this form of demonstration. The answers include brief notes on diagnosis and treatment, and at the end of the book there are summaries of some recent developments in medical treatment. This volume is the first of a series. Medical Electronics G. E. DONOVAN, M.D., M.SC., D.P.H. London: Butterworth. 1953. Pp. 215. 30s. THE aim of this book is " primarily to provide a bird’s eye view of the uses of electronics in medicine." The list of contents is impressive, including such subjects as X rays, radioactive isotopes, television, electron microscopy, amplifiers, phono-electrocardioscopy, electromyography, servo mechanisms, and cybernetics. But in his effort to cover so much ground so quickly the author does not always carry the reader along with him. Much electronic terminology is used without additional or simplifying explanation : "the p-n-p junction triode," ’’ frequency selector and clipper, pulse shaper and delay circuit," and " the usual arrangement of push-pull stages with cathode degeneration of in-phase voltages " are phrases unlikely to convey any clear idea to those not engaged in electronic work. The almost complete absence of crossreferences is tiresome : thus a porous-plug transducer is mentioned on p. 88 but not in the chapter on transducers, while gas amplification is not explained in the chapter on photo-electric cells, though the reader is told earlier that gas amplification does not take place in ionisation chambers. The illustrations are of mixed quality : some, such as those in the chapter on electron microscopy, are good, especially the comparison between the electron microscope and the optical microscope ; others, showing merely the outside appearance of cabinets, are unhelpful. Dr. Donovan believes that detailed circuit diagrams are not necessary for an understanding of the principles involved in an apparatus, and that may be so ; but there is still a real need for the imaginative use of block schematic diagrams. The preface suggests that doctors who are not already familiar with the applications of electronics to medicine may find the book of interest ; but those-who are not well versed in electronic teminology will find much of it perplexing-though they may profit from the accounts of the various applications. Physicists, research-workers, and electronic engineers will find some useful references.
Treatment with radioactive iodine seemed indicated, and Sept. 11, 1951, a dose of 20 mC was given by mouth. Of this 56% was excreted in forty-eight hours, the uptake in the chest reaching 35% in twenty-four hours. Two months later a fourth tracer dose showed a maximal uptake in the chest of 46% at twenty-four hours, and a second treatment dose was then given, this time of 102 mC. A fairly prolonged radiation sickness followed this, and the patient did not recover normal vitality for about two months. Transient lymphopenia developed but no dangerous depression of the
formance of objective tests of lung function ; and it has been confirmed by definite clearing of the X-ray shadows in the lungs. (I am indebted to Dr. G. Simon for the interpretation of these films.)
Summary
on
marrow.
A further tracer study on June 19, 1952, nine months after this last treatment, showed that the uptake by the lungs had now risen still further, reaching 56% of the dose at twentyfour hours, with no demonstrable uptake in the neck. Calculation (Oddie 1951) showed that the therapeutic doses should have provided local irradiation of about 10,000 r.e.p. throughout the lungs. It seemed that effective ablative doses of radioactive iodine would have to be prohibitively high, and X-ray therapy also, if an adequate response were to be obtained. Treatment with thyroxine was therefore started in the hope that the metastases might behave like nodular goitre and slowly regress. L-thyroxine was used because it contains less non-hormonal iodine than does the racemic form, and less than thyroid extract, and would not therefore interfere with any subsequent tracer studies. Sodium-1-thyroxine was started on July 16, 1952, in a dosage of 01 mg. daily, which was slowly increased until by Oct. 7 the patient was receiving 10 mg. daily, with the production of signs of mild toxicity. The dosage was reduced to 07 mg. daily, at which level no symptoms were produced, and the patient was then readmitted for further tracer studies. On Dec. 15, 1952, 99% of an intravenous tracer dose was excreted in forty-eight hours, without any demonstrable uptake either in the chest or in the neck. Thyroxine was then discontinued, and four weeks later, on Jan. 12, 1953, the patient was readmitted for further study. She now presented the typical appearance of hypothyroidism ; the uptake of radio-iodine in the chest reached 26% of the dose at twenty-four hours, with no demonstrable concentration elsewhere. Further Progress.-Since then she has been maintained on thyroxine, without intermission, in a dosage of 0-5 mg. daily. There has been a slow but considerable reduction in dyspnoea ; the lung-function tests have been repeated and show a rise in the maximal breathing capacity, from 47 litres a minute to 79 litres a minute, although the vital capacity has remained unaltered at 2070 c.cm. ; and there is now a slight but definite clearing of the X-ray shadows in the lungs.
Discussion Dr. I am indebted to G. J. Cunningham for his report on the histology of the local recurrence in the neck. The tumour here was well differentiated, and it is likely that the pulmonary metastases are similar to it. This is confirmed by the ability of the pulmonary metastases to pick up iodide, as the tracer studies showed ; and the patient’s euthyroid state despite total thyroidectomy was presumably attributable to their activity. The suppression of iodide uptake after treatment with thyroxine parallels that observed in healthy people both in its degree and in its duration (Greer 1951, Morgans et al. 1952). It was followed by a phase of rebound hypothyroidism, as in healthy people (Farquharson and Squires 1941). It is reasonable to suppose that the mechanism of this lies in the suppression, by the administered hormone, of the pituitary output of thyrotrophic hormone, as in healthy people, and the resultant diminution in activity of the thyroid gland. This would indicate the dependence of the pulmonary thyroid tissue on normal thyrotrophic stimulation from
the pituitary.
Regression of the metastases after treatment thyroxine was shown by clinical improvement, lessening of dyspn(Ea subjectively and a better
with with per-
A case of well-differentiated thyroid carcinoma is described in which very numerous functioning deposits in the lungs proved resistant to treatment with radioactive iodine, but now appear to have been satisfactorily suppressed as a result of prolonged treatment with
thyroxine. This patient was in the first place under the care of Mr. 1. G. Williams, and my thanks are due to him and to Dr. A. E. Jones for permission to publish her case. As an inpatient she was under the care of Prof. R. V. Christie, to whom I am grateful for permission to publish and for help with the preparation of this paper. The radio-iodine studies were undertaken by the Department of Physics, and I am indebted to Prof. J. Rotblat and to Mr. G. M. Owen for the great deal of careful work they have done. REFERENCES
Danowski, T. S., Huff, S. J., Tarail, R., Wirth, P., Peters, J. H., Mateer, F. M., Garver, K. (1952) J. clin. Endocrin. 12, 1572. Farquharson, R. F., Squires, A. H. (1941) Trans. Ass. Amer. Phycns, 56, 87. Greer, M. A. (1951) New Engl. J. Med. 244, 385. Astwood, E. B. (1953) J. clin. Endocrin. 13, 1312. Morgans, M. E., Oldham, A. K., Trotter, W. R. (1952) J. Endocrinol 8, 250. Oddie, T. H. (1951) Brit. J. Radiol. 24, 333. Perlmutter, M., Weisenfeld, S., Slater, S., Wallace, E. Z., David, M. M. (1952) J. clin. Endocrin. 12, 208. Riggs, D. S., Man, E. B., Winkler, A. W. (1945) J. clin. Invest. 24, 722. —
Preliminary
Communication
TOXOPLASMOSIS IN CHILDHOOD PATIENTS with
unexplained pyrexia
of
7-10
days
duration accompanied by generalised lymphadenopathy and sometimes by a rash and splenomégaly are commonly seen in the outpatient department of a children’s hospital. A blood-count shows a leucocytosis of 10,000-15,000 per c.mm. with an increase in the proportion of polymorph cells, a threefold or fourfold increase in the absolute eosinophil-count, and no glandular fever " cells. The Paul-Bunnell test is negative despite a reasonable clinical diagnosis of infectious mononucleosis. Throughout the world it has been found that up to 50% of apparently normal adults have a positive dye test for toxoplasmosis, while less than 10% have complement-fixing antibodies. In toxoplasmosis the complement-fixation test is believed to become positive later, and its titre to fall more quickly, than does the dye test. Although domestic animals are presumed to be the reservoir of infection, apart from congenital toxoplasmosis little is known of how or when man becomes infected with toxoplasmas or whether the initial exposure to the parasite, leading to the production of antibodies, is invariably unassociated with symptoms. The lack of explanation for the numbers of cases of children with pyrexia and lymphadenopathy, and their resemblance to known cases of acquired toxoplasmosis, "
RESULTS OF DYE TEST AND COMPLEMENT-FIXATION TEST IN 20 CASES OF CHILDREN WITH UNEXPLAINED PYREXIA AND LYMPHADENOPATHY
814 led me to wonder whether this condition might represent the first, antibody-stimulating exposure to toxoplasmas, resembling a primary tuberculous complex. INVESTIGATION
Sera from 20 children and young adults suspected on clinical grounds of having glandular fever were all found to give a negative Paul-Bunnell test. Toxoplasma dye and complement-fixation tests were made, and the findings are shown in the accompanying table. COMMENT
These results were unexpected, because of both the number of positive findings and of the high titres. It is Still difficult to know, in the absence of recognised signs of toxoplasmosis, what attention to pay to positive serological findings, but a titre of 1/8 for the complementfixation test is generally regarded as of some diagnostic significance. Of the 20 cases 6 had titres in excess of this ; while in a 7th case where the serum was anticomplementary the dye-test titre was 1/256-four times as high as that usually found in the symptomless adult. These preliminary findings are far too incomplete for any firm conclusions. A much larger series of cases of glandular enlargement must be investigated, and a long follow-up is being undertaken to observe changes in antibody titre. Also the haematological findings must be accurately correlated with the serological. But the present data do lend support to the belief that some, at least, of the cases of apparently non-specific generalised lymphadenopathy with pyrexia in children may be due to toxoplasma infection, and that the positiveserological tests so often found in the symptomless adult may be a residuum of such infection. The Hospital for Sick Children, I. A. B. CATHIE Great Ormond Street, London
M.D. Lond., M.R.C.P.
Reviews of Books Rh-Hr Blood
Types Applications in Clinical and Legal pology. ALEXANDER S. WIENER,
Medicine and AnthroM.D., F.A.C.P., senior to the office of the chief medical examiner of Stratton. 1954. New York City. New York : Grune &
serologist
Pp. 763. $11.50. An Rh-Hr Syllabus The Types and their Applications. ALEXANDER S. WIENER. New York : Grune & Stratton. 1954. Pp. 82.$3.75.
BETWEEN 1929 and 1953 Dr. Wiener and his co-workers 333 papers on the Rh-Hr blood types. The first of the two volumes reviewed here gives a, full list arranged in years. The papers have appeared not only in the United States but also in British, French, and Italian journals and some others. From these numerous and often important writings Dr. Wiener has selected 84 to represent his contribution to every aspect of the subject. As they have been reproduced from the originals by a photographic process, the book inevitably contains a mixture of sizes and shapes of type which makes for difficult reading ; sometimes the reproduction is not too clear and some of the more complex tables need a magnifying-glass. It may be useful to have this collection under one cover, but the relatively few experts directly interested in the subject are likely to have read the principal papers already and probably possess reprints. The non-expert will hardly tackle so difficult a set of papers, and in his Rh-Hr Syllabus Dr. Wiener himself has in fact provided them with a much shorter and simpler account of his work. The Syllabus is an excellent little monograph, containing all that anyone not actually pursuing research into blood-groups needs to know about the Rh-Hr blood-group system and the pathological conditions in which it is concerned. It begins with a series of definitions of fundamentals, and the next two chapters, on Rh antibodies and on the serology and genetics of
published
i
the Rh-Hr types, contain short didactic discussion, illustrated by clear diagrams. A fairly long and remark. ably informative chapter on erythroblastosis fœtalis is followed by short chapters on blood-transfusion, anthropology, and medicolegal applications. Unfortunately Dr. Wiener’s views on nomenclature introduce difficulties for many of the readers who would benefit most from his book. In this country the CDE n menclature is in everyday use; but, as is well known, Dr. Wiener regards it as misguided and misleading, and will have none of it. As things stand, the ordinary student needs the help of books that, unlike Dr. Wiener’s, make But it is a a fair job of collating the two systems. measure of his skill that he makes his subject plain despite the complexity of the notation which the devotees of the theory of multiple alleles find necessary for’the expression of their ideas.
Spot Diagnosis Volume, 1. Compiled by the Editors of Medicine Illustrated. London: Harvey & Blythe. 1954. Pp. 128. 7s. 6d. THIS is an entertaining and teasing book. The reader is invited to examine a photograph and consider some clues ; he must then make a diagnosis, and answer some questions, before turning to the right answer on the next page (rather too handy for those who readily succumb to temptation). Most of the pictures have appeared under similar examination conditions in Medicine Illtistrated. The game is both instructive and aggravating ; for the baffled diagnostician learns from his mistakes, yet complains that he would have done better, of course, in the flesh or with a coloured photograph. And he may be annoyed when a non-fluctuant swelling turns out to be a cold abscess, even though the answer generously excuses him from blame in this case. One or two of the conditions are on the rare side, but then many of the commoner diseases do not lend themselves to this form of demonstration. The answers include brief notes on diagnosis and treatment, and at the end of the book there are summaries of some recent developments in medical treatment. This volume is the first of a series. Medical Electronics G. E. DONOVAN, M.D., M.SC., D.P.H. London: Butterworth. 1953. Pp. 215. 30s. THE aim of this book is " primarily to provide a bird’s eye view of the uses of electronics in medicine." The list of contents is impressive, including such subjects as X rays, radioactive isotopes, television, electron microscopy, amplifiers, phono-electrocardioscopy, electromyography, servo mechanisms, and cybernetics. But in his effort to cover so much ground so quickly the author does not always carry the reader along with him. Much electronic terminology is used without additional or simplifying explanation : "the p-n-p junction triode," ’’ frequency selector and clipper, pulse shaper and delay circuit," and " the usual arrangement of push-pull stages with cathode degeneration of in-phase voltages " are phrases unlikely to convey any clear idea to those not engaged in electronic work. The almost complete absence of crossreferences is tiresome : thus a porous-plug transducer is mentioned on p. 88 but not in the chapter on transducers, while gas amplification is not explained in the chapter on photo-electric cells, though the reader is told earlier that gas amplification does not take place in ionisation chambers. The illustrations are of mixed quality : some, such as those in the chapter on electron microscopy, are good, especially the comparison between the electron microscope and the optical microscope ; others, showing merely the outside appearance of cabinets, are unhelpful. Dr. Donovan believes that detailed circuit diagrams are not necessary for an understanding of the principles involved in an apparatus, and that may be so ; but there is still a real need for the imaginative use of block schematic diagrams. The preface suggests that doctors who are not already familiar with the applications of electronics to medicine may find the book of interest ; but those-who are not well versed in electronic teminology will find much of it perplexing-though they may profit from the accounts of the various applications. Physicists, research-workers, and electronic engineers will find some useful references.