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Page 335 - The experiments which have been detailed lead to the following conclusions. 1. Alcohol, the essential oil of almonds, the juice of aconite, the empyreumatic oil of tobacco, and the woorara, act as poisons by simply destroying the functions of the brain; universal death taking place, because respiration is under the influence of the brain, and ceases when its functions are destroyed.
Page 371 - When a tree which requires much moisture (says Mr. Knight) has sprung up or been planted in a dry soil, in the vicinity of water, it has been observed that a much larger portion of its roots has been directed towards the water ; and that when a tree of a different species, and which requires a dry soil, has been placed in a similar situation, it has appeared, in the direction given to its roots, to have avoided the water and moist soil."f
Page 371 - That, when the influence of the brain is cut off", the secretion of urine appears to cease, and no heat is generated ; notwithstanding the functions of respiration, and the circulation of the blood, continue to be performed ; and the usual changes in the appearance of the blood are produced in the lungs. 4. That, when the air respired is colder than the natural temperature of the animal, the effect of respiration is not to generate but to diminish animal heat.
Page 333 - ... the influence of the brain to be necessary, was not generated. Having learned that the circulation might be kept up by artificial respiration for a considerable time after the woorara had produced its full effects, it occurred to me, that, in an animal under the influence of this or of any other poison that acts in a similar manner, by continuing the artificial respiration for a sufficient length of time after natural respiration had ceased, the brain might recover from the impression which the...
Page 302 - ... injection. Immediately after respiration had ceased, I opened the thorax, and found the heart extremely distended, and without any evident contraction, except of the appendix of the right auricle, which every now and then contracted in a slight degree. I divided the pericardium on the right side. In consequence of the extreme distension of the heart, this could not be done without irritating the fibres with the point of the scalpel. Immediately both auricles and ventricles began to contract with...
Page 303 - We may conclude from these experiments, that the effect of the infusion of tobacco, when injected into the intestine of a living animal, is to destroy the action of the heart, stopping the circulation and producing syncope. It appeared to me that the action of the heart ceased even before the animal had ceased to respire ; and this was confirmed by another experiment, in which, in a dog killed by the infusion of tobacco, I found the cavities of the left side of the heart to contain scarlet blood,...
Page 325 - The woorara is a poison, with which the Indians of Guiana arm the points of their arrows. It appears not to differ essentially • from the ticunas, which was employed in the experiments of the Abbe Fontana.
Page 235 - ... to assist the progress of discussion, and to diffuse just ideas on the subject. If the great discoverer of this substance had signified it by any simple name, it would have been proper to have recurred to it ; but, dephlogisticated marine acid is a term which can hardly be adopted in the present advanced aera of the science.
Page 327 - On opening the chest, the heart was found to have entirely ceased contracting; it was much. distended with blood ; and the blood in the cavities of the left side was of a scarlet colour. On irritating the heart with the point of the scalpel, the ventricles contracted, but not sufficiently to restore the circulation.
Page 302 - Immediately there took place tremulous contractions of the voluntary muscles. Five minutes afterwards the injection was repeated in the same quantity. The dog then was sick, and threw up some of the infusion, with other matter, from the stomach ; he became faint, and died ten minutes after the second injection. Immediately after respiration had ceased, I opened the thorax, and found the heart extremely distended, and without any evident contraction, except of the appendix of the right auricle, which...