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PERSPECTIVES IN EVOLUTION
1228 evidence that blood stored for be used
successfully,
a month or more can continuous drip transfew and bear no relation
even as a
and that reactions are to the length of storage (Hamilton-Paterson 6). Clearly, if cell haemoglobin is neither excreted in the urine nor converted into urobilin, it must remain in the blood and be available for oxygen carriage. It appears that stored blood is of great value in severe acute hemorrhage, useful in the anagmia of chronic haemorrhage, but probably contra-indicated in agranulocytosis and the blood diseases; and it must be remembered that, while in peace-time the blood bank is a convenience, in war-time it is a necessity.
fusion,
PAREDRINE
IN SPINAL ANÆSTHESIA
MOST of those who make frequent use of spinal analgesia are troubled sooner or later by the profound drop in blood-pressure which is sometimes associated with it. The physiological mechanism by which this fall is brought about has been the subject of much controversy but nearly all are agreed on its occasionally serious effects. The drugs used to counteract the
fall, chiefly epinephrine and ephedrine, are not always successful. Now a new agent has been introduced in the United States, and so far as can be judged from the small number of patients on whom it has been used it promises to be effective. It is called Paredrine and is p-hydroxy-a-methyl-phenyl-ethylamine-hydrobromide. In a series reported by Altschule and Gilmanparedrine was given to 50 patients in whom there was rapid and considerable fall in blood-pressure during spinal anaesthesia. They gave either 10 to 20 mg. intramuscularly or 5 to 10 mg. intravenously In every instance the administration was or both. followed by the return of blood-pressure to a satisfactory level. The rise usually began within five minutes of the introduction of the drug and lasted No untoward symptoms from 20 to 50 minutes. Paredrine causes none of the cortical were observed. action which accompanies the use of benzedrine and its effect is more lasting than that of epinephrine. It appears to act almost entirely on the peripheral vessels, without increasing the output of the heart. PERSPECTIVES IN EVOLUTION
IN his address to the section of zoology of the British Association, now published,s Prof. James Ritchie begins by glancing at the difference between pure and economic science. Economic science seems to mean knowledge that directly advances man’s comfort and happiness, and out of which someone, though not necessarily the discoverer, may make money; while pure science is knowledge which up to now has not shown the same adaptability; though, of course, it may do so at any time. Then he passes to the secret of life, and one gathers that at heart he is a mechanist-which seems the up-to-date term for materialist-rather than a vitalist, for he points out how the kernel of animation, vitalism or life has retreated further and further into its shell before the attacks of the chemists and physicists. But he is very fair and recognises that no one as yet has made artificial protoplasm react by motion to any stimulus; and that, he thinks, is the prerogative of life. Viewing the quality of life in perspective, he gives some startling facts. Sea water, he says, contains only 0.12 part of calcium carbonate per thousand, yet some 6. Hamilton-Paterson, J. L., Brit. med. J. Nov. 4, 1939, p. 908. 7. Altschule, M. D., and Gilman, S., New Eng. J. Med. Oct. 19,
1939, p. 600. 8. First Quarterly Report of the British Association’s Dundee Meeting, September 1939. Published by the Association at Burlington House, W.1. Pp. 154. 5s.
48 million square miles of the ocean floor are covered with a deep deposit of calcareous ooze, containing calcium carbonate up to 90 per cent., extracted by marine animalcules from the sea. Then again the lower atmosphere contains only about 3 parts in ten thousand of carbon dioxide, yet all our peat, coal, oil shale and natural petroleum have been collected from this diffused store by plants. A single tree, five tons in weight, has absorbed the carbon dioxide from 16,125,000 cubic yards of air for its growth. These figures are quoted to emphasise the great law that: "While, left to themselves, the units of matter in a gas or solution move towards their greatest dispersal, when they are in contact with living organisms this dispersal is replaced by assortment and aggregation." Not even a bacterium satisfies Professor Ritchie as the earliest form of life; he is forced to postulate some precellular, diffuse material whose one outstanding character is the power of using for its own aggrandisement some form of energy external to it. And thus the vitalists still hold their fort. His account of the way in which the estimated age of the earth has increased of late years is amusing. In Bagster’s "Polyglot Bible," working on the genealogies recorded in Genesis, the date of the creation was fixed at B.C. 4004. Buffon, in the eighteenth century, said that the age of the earth was 75,000 years. Lord Kelvin, in the nineteenth, suggested 20 to 40 million years. Sir Archibald Geikie, in 1899, required not much less than 100 million years since the earliest forms of life appeared and perhaps 400 million since the world began, while the present view is that the birth of the earth, and possibly that of the solar system, took place 2000 million years ago. He next discusses the slowness of the process of evolution. The edible cockle has retained its specific characters for 2 million years, while the transition of the four-toed horse (Eohippus) to our own one-toed animal took 57 million years. On the other hand, there seems little doubt that certain species of mice and voles have been evolved since the last glacial period, a trifling 22,000 years ago. Man of our own species has probably less than a million years behind him though he did not take his place as the lord of creation until Neolithic times, which only reached Western Europe some 8000 years B.C. With regard to the immediate future-immediate from a geological point of view-the higher intellectual, spiritual and moral condition of man seems likely to continue its advance, and in these days the probability is welcome; but Professor Ritchie wisely points out that 180 million years ago the great dinosaurs were the lords of creation, and where are they now? Looking forward to the next 100 million years, he says: " It is presumptuous to suppose that man, the latest new-comer, is the last word. It is worth while to look on him in his biological setting as but one, though so far the greatest, of the manifestations of life upon the earth." MASS TESTING OF COLOUR VISION
THE investigation of colour vision takes a long time and needs expensive apparatus and expert examiners, so that it cannot easily be included in many routine medical examinations of which it would be a useful part. Berens and Steinhave now devised an ingenious but simple method for testing the colour vision of a large number of people at one session. The standard Ishihara and Stillings charts are photographed on 35 mm. Kodachrome film, from which copies can readily be made. From this coloured lantern slides 2 in. square are made to fit a miniature projector 1.
Berens, C., and Stein, L., J. Amer. med. Ass. 1939, 113, 1563.
successfully,
a month or more can continuous drip transfew and bear no relation
even as a
and that reactions are to the length of storage (Hamilton-Paterson 6). Clearly, if cell haemoglobin is neither excreted in the urine nor converted into urobilin, it must remain in the blood and be available for oxygen carriage. It appears that stored blood is of great value in severe acute hemorrhage, useful in the anagmia of chronic haemorrhage, but probably contra-indicated in agranulocytosis and the blood diseases; and it must be remembered that, while in peace-time the blood bank is a convenience, in war-time it is a necessity.
fusion,
PAREDRINE
IN SPINAL ANÆSTHESIA
MOST of those who make frequent use of spinal analgesia are troubled sooner or later by the profound drop in blood-pressure which is sometimes associated with it. The physiological mechanism by which this fall is brought about has been the subject of much controversy but nearly all are agreed on its occasionally serious effects. The drugs used to counteract the
fall, chiefly epinephrine and ephedrine, are not always successful. Now a new agent has been introduced in the United States, and so far as can be judged from the small number of patients on whom it has been used it promises to be effective. It is called Paredrine and is p-hydroxy-a-methyl-phenyl-ethylamine-hydrobromide. In a series reported by Altschule and Gilmanparedrine was given to 50 patients in whom there was rapid and considerable fall in blood-pressure during spinal anaesthesia. They gave either 10 to 20 mg. intramuscularly or 5 to 10 mg. intravenously In every instance the administration was or both. followed by the return of blood-pressure to a satisfactory level. The rise usually began within five minutes of the introduction of the drug and lasted No untoward symptoms from 20 to 50 minutes. Paredrine causes none of the cortical were observed. action which accompanies the use of benzedrine and its effect is more lasting than that of epinephrine. It appears to act almost entirely on the peripheral vessels, without increasing the output of the heart. PERSPECTIVES IN EVOLUTION
IN his address to the section of zoology of the British Association, now published,s Prof. James Ritchie begins by glancing at the difference between pure and economic science. Economic science seems to mean knowledge that directly advances man’s comfort and happiness, and out of which someone, though not necessarily the discoverer, may make money; while pure science is knowledge which up to now has not shown the same adaptability; though, of course, it may do so at any time. Then he passes to the secret of life, and one gathers that at heart he is a mechanist-which seems the up-to-date term for materialist-rather than a vitalist, for he points out how the kernel of animation, vitalism or life has retreated further and further into its shell before the attacks of the chemists and physicists. But he is very fair and recognises that no one as yet has made artificial protoplasm react by motion to any stimulus; and that, he thinks, is the prerogative of life. Viewing the quality of life in perspective, he gives some startling facts. Sea water, he says, contains only 0.12 part of calcium carbonate per thousand, yet some 6. Hamilton-Paterson, J. L., Brit. med. J. Nov. 4, 1939, p. 908. 7. Altschule, M. D., and Gilman, S., New Eng. J. Med. Oct. 19,
1939, p. 600. 8. First Quarterly Report of the British Association’s Dundee Meeting, September 1939. Published by the Association at Burlington House, W.1. Pp. 154. 5s.
48 million square miles of the ocean floor are covered with a deep deposit of calcareous ooze, containing calcium carbonate up to 90 per cent., extracted by marine animalcules from the sea. Then again the lower atmosphere contains only about 3 parts in ten thousand of carbon dioxide, yet all our peat, coal, oil shale and natural petroleum have been collected from this diffused store by plants. A single tree, five tons in weight, has absorbed the carbon dioxide from 16,125,000 cubic yards of air for its growth. These figures are quoted to emphasise the great law that: "While, left to themselves, the units of matter in a gas or solution move towards their greatest dispersal, when they are in contact with living organisms this dispersal is replaced by assortment and aggregation." Not even a bacterium satisfies Professor Ritchie as the earliest form of life; he is forced to postulate some precellular, diffuse material whose one outstanding character is the power of using for its own aggrandisement some form of energy external to it. And thus the vitalists still hold their fort. His account of the way in which the estimated age of the earth has increased of late years is amusing. In Bagster’s "Polyglot Bible," working on the genealogies recorded in Genesis, the date of the creation was fixed at B.C. 4004. Buffon, in the eighteenth century, said that the age of the earth was 75,000 years. Lord Kelvin, in the nineteenth, suggested 20 to 40 million years. Sir Archibald Geikie, in 1899, required not much less than 100 million years since the earliest forms of life appeared and perhaps 400 million since the world began, while the present view is that the birth of the earth, and possibly that of the solar system, took place 2000 million years ago. He next discusses the slowness of the process of evolution. The edible cockle has retained its specific characters for 2 million years, while the transition of the four-toed horse (Eohippus) to our own one-toed animal took 57 million years. On the other hand, there seems little doubt that certain species of mice and voles have been evolved since the last glacial period, a trifling 22,000 years ago. Man of our own species has probably less than a million years behind him though he did not take his place as the lord of creation until Neolithic times, which only reached Western Europe some 8000 years B.C. With regard to the immediate future-immediate from a geological point of view-the higher intellectual, spiritual and moral condition of man seems likely to continue its advance, and in these days the probability is welcome; but Professor Ritchie wisely points out that 180 million years ago the great dinosaurs were the lords of creation, and where are they now? Looking forward to the next 100 million years, he says: " It is presumptuous to suppose that man, the latest new-comer, is the last word. It is worth while to look on him in his biological setting as but one, though so far the greatest, of the manifestations of life upon the earth." MASS TESTING OF COLOUR VISION
THE investigation of colour vision takes a long time and needs expensive apparatus and expert examiners, so that it cannot easily be included in many routine medical examinations of which it would be a useful part. Berens and Steinhave now devised an ingenious but simple method for testing the colour vision of a large number of people at one session. The standard Ishihara and Stillings charts are photographed on 35 mm. Kodachrome film, from which copies can readily be made. From this coloured lantern slides 2 in. square are made to fit a miniature projector 1.
Berens, C., and Stein, L., J. Amer. med. Ass. 1939, 113, 1563.