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In our examination of the work before us, we shall endeavour to present to our readers a clear view of the facts and deductions of the author, with an occasional comment upon some of the opinions which he has advanced. We shall follow, however, a somewhat different arrangement from that adopted by Dr. Beaumont.The subject upon which the experiments of the latter were performed, Avas a young man, of a good constitution, robust and healthy, who, on the Gth of June, 1822, he being then eighteen years of age, was accidentally wounded by the discharge of a musket loaded with buck-shot. The load entered his body posteriorly, and in an oblique direction, forwards and inwards, literally blowing off a portion of the integuments and muscles ofihe size of a man's hand, fracturing and carrying away the anterior half of the sixth rib ; fracturing the fifth ; lacerating the lower portion of the left lobe of the lungs and the diaphragm, and perforating the stomach. On examination, twenty-five or thirty minutes after the accident, a portion of the lung, as large as a turkey's egg, was found protruding through the exterior wound, lacerated and burnt, and immediately below this, was " another protrusion, which, on further examination, proved to he a portion of the stomach, lacerated through all its coats, and pouring out the food " that had been eaten in the morning, "through an orifice large enough to admit the forefinger."It is unnecessary, on the present occasion, to follow out the surgical details of the accident and its treatment. For seventeen days every thing that was taken by the mouth soon passed out at the wound, and the only manner in "which the patient was sustained was by nutritious injections per anum. During this period alvine evacuations could not be obtained, notwithstanding cathartic enemata were given, and various other means adopted to promote them. As soon, however, as compresses and adhesive straps could be applied over the opening into the stomach, and food was retained in the latter, by the aid of purgative injections, a very hard, black, fetid stool was procured, followed by several similar ones ; after which the bowels became quite regular, and continued so." No sickness, nor unusual irritation of the stomach, not even the slightest nausea, was manifest during the whole time; and after the fourth week, the appetite became good, digestion regular, the alvine evacuations natural, and all the functions of the system perfect and healthy.By the adhesion of the sides of the protruded portions of the stomach to the pleura costalis and the external wound, a free exit was afforded to the contents of that organ, and effusion into the abdominal cavity was thereby prevented."Cicatrization and contraction of the external wound commenced in the fifth Week; the stomach became more firmly attached to the pleura, but the orifice * Not having been able to procurc a copy of Dr. Beaumont's work in time for this Number of the Journal, we have transferred to our columns an admirable analysis of it from a recent Number of our e...

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Variations in erythrocyte volume [mean corpuscular volume (MCV)] were evaluated during exercise and heat stress to determine the influence on calculated plasma volume and content changes. The results of this study on 17 men indicate that the human red blood cell can increase, decrease, or remain constant in volume during physical stress depending on the combined interactions of plasma osmolality and blood pH. Shrinking of MCV can occur when the increase in plasma osmolality is larger than 5 mosmol/kg H2O and the blood pH remains within 0.1 pH units of its resting value. Erythrocyte swelling is usually noticed with maximal exercise when the blood pH is less than 7.10, in spite of 20 mosmol/kg H20 increments in plasma osmolality. The regression equations indicate that during 30 min of exercise in a cool environment the plasma shifts calculated by either the hematocrit or the hematocrit + hemoglobin method fall within 1% of each other, but during resting heat exposure the hematocrit technique under-estimates the fluid shift by 2.5-3.0%. Application of these considerations to the calculation of plasma content changes during stress made it clear that the pattern of plasma potassium content is quite different with maximal as compared with submaximal exercise.

been purified approximately 300 fold by absorption and elution from diethylaminoethyl (DEAE) cellulose (12) followed by precipitation with 55-percent saturation of ammonium sulfate at 0?C. Moreover, when DEAE cel? lulose is developed with a linear NaCl gradient, the corresponding variant and normal LDH isozymes are eluted at similar points. The mobility of normal and variant LDH isozymes from crude hemolyzates is identical in the sys? tem (75) of varying starch-gel porosity. Such behavior suggests that the molecular weight of normal and variant isozymes is grossly similar (14). The enzymic activity of variant LDH from crude hemolyzate approximates that ob? served in normal American and Nigerian Negroes. The only blood relative available for testing, a paternal uncle, has a normal LDH pattern. Whatever the origin of the observed LDH variation, it is uncommon (75) since no variant LDH patterns were observed among hemo? lyzates obtained from approximately 50 white subjects, 300 American Negroes, 100 Papuans (16), and 200 Nigerians. Fritz and Jacobson (17) examined mouse tissue extracts and observed five LDH-5 components, four LDH-4 com? ponents, three LDH-3 components, two LDH-2 components, and one LDH-1 component in gels prepared with 0.005M /?-mercaptoethanol. These au? thors suggest that this concentration of /?-mercaptoethanol removes bound NAD from a portion of A subunits but not from B subunits. These ob? servations provide a pattern exactly opposite to that in the Nigerian LDH variant. Moreover, the human variant LDH pattern is unaltered in gels con? taining /3-mercaptoethanol in amounts ranging from 0.005 to 0.1M. The vari? ant LDH pattern is also unaltered by electrophoresis under conditions where the gel and cathodic chamber contain 10~3M NAD. Accordingly, we do not believe that the variant pattern is pro? duced by the mechanism of differential binding of NAD. The variant electrophoretic pattern can be most easily interpreted as reflect? ing a mutant allele at the genetic locus producing the LDH B subunit. The observed physical and enzymatic similarities between normal and variant LDH-1, that is, B subunit tetramers, support this interpretation. If the mu? tant product is designated /?, and the normal product B, then a heterozygote at this locus should exhibit the combi? nations shown in the third column of As work continues the sweating rate may then be controlled by thermal factors, such as increased core or hypothalamic temperatures. In cooler environments the same nervous stimuli may be present, but inefTective because of inhibition by the cooler temperature (77).

Fluid and electrolyte shifts were measured in seven men (19-21 yr) during three 2-wk bed rest (BR) periods, each of which was separated by a 3-wk ambulatory recovery period. During two of the three BR periods they performed isometric exercise and isotonic exercise. No prescribed exercise was given during the other BR period. On day 4 of BR, plasma volume decreased (P less than 0.05) 441 ml (-12.6%) with no exercise, 396 ml (-11.3%) with isometric, and 262 ml (-7.8%) with isotonic exercise; the decreases (NS) of extracellular volume were -4.4%, -2.6%, and -2.7%, respectively. By day 13 of BR, plasma volume stabilized at the lower level with isometric and isotonic exercise and continued to decline with no exercise; but the extracellular volume returned to or above control levels due to an overshoot of the interstitial volume of +320 to +430 ml (2.0-2.7%) that was about equal to the plasma volume loss. During BR there were isocontent losses from the plasma of protein, albumin, globulin, urea N2, uric acid, creatinine, Na, Cl, osmolarity, P, and glucose that were not influenced by either exercise regimen. However, the blood, red blood cell, and plasma volumes, and the Ca and K contents were stabilized during BR by both exercise regimens. The results suggest that during BR, preservation of the extracellular volume takes precedence over maintenance of the plasma volume, and this mechanism is independent of the effects of isometric or isotonic exercise.