LABOURERS in factories in South Malaya who cut up pineapples by hand for canning invariably show an abnormality of those parts of the body which are exposed to slight pressure and pineapple juice, notably the palmar surfaces of the fingertips and the periphery of the palms. At the beginning of the canning season, the left hand, which comes more into contact with the fruit than the knife-holding hand, becomes sore and small superficial raw areas on the fingertips are often seen. Within several days, however, these heal, and the skin ceases to be sore. The labourers state that this tolerance to the pineapple juice is due to the development of an abnormality of the skin, which in the affected area becomes bluish-white and so smooth that fingerprints may be completely lost. Deep cracks are sometimes seen in the region of the skin creases. These often stay raw and bleeding for a long time, and show no clinical signs of infection, presumably because of removal of dead tissues by enzymatic action.
BEFORE Sir Ronald Ross's epoch-making discovery, there was no more puzzling problem in medicine than the cause of malaria; no secret in Nature more cunningly hid than the malaria secret. Malaria was known to be connected with swamps, and to be reduced by drainage and cultivation. Yet, as if merely to confuse, men found that to flood some swamps actually improved health; and elsewhere that drainage and the cultivation of the soil produced the most serious and devastating outbursts of the disease. Yet again, malaria was found not only in swamps, but also often on hills and dry sandy deserts. Some jungle-covered land was singularly free from malaria: other jungle land was intensely malarial. In fact, malaria existed on soils of every conceivable variety, of every age in geological time. It was-impossible to point to any mineral, chemical, or vegetable condition essential to its presence. It was, and had been for hundreds of years, a dark, inscrutable mystery.
DR. WATSON'S book shows clearly the wide range of scientific knowledge which is required by those who work in the tropics either as physicians or as sanitarians. It is unnecessary nowadays to insist upon the importance of the control of malaria in the development of those vast areas from which is derived so much of the food supplies and raw materials of manufacture of all civilised countries, but only those who have had practical experience of the methods used to deal with the disease can appreciate how many and how varied these must be.
ANTHROPOLOGISTS are again indebted to Mr. Ling Roth for presenting to them, in a convenient form, the results of wide reading and diligent compilation. It is by such well-directed enthusiasm that the labours of the student are materially lightened; for not only has the author, in this instance, marshalled a portentous array of accurately acknowledged quotations, but he has sedulously collected illustrations of objects preserved m numerous museums and private collections, in order to fully illustrate the descriptions that he quotes.