This case seems conclusive upon the matter, for if Mr. Wood, entirely abstaining from all liquids, except such as were used in the formation of his boiled puddings, or were imbibed by them during cooking, voided a pint and a half of urine daily, it may be conceded that the urine of a person suffering from diabetes mellitus may much exceed the amount of liquids drank, when we consider the very large quantity of cooked food of all kinds he takes during the day. . THE distinguished Muller states,

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... n his well-known and excellent work on Physiology-" I confess that the act of absorption in other parts, as well as in the intestines, is to me quite an enigma." And again: "The powers by which the lymph and chyle are moved are unknown." When I first entered upon medical studies, the perusal of the standard works on anatomy and physiology &c. which were placed in my hands, at once forced upon my mind the fact, that the profession had, age after age, pursued those sciences without having previously made themselves acquainted with the principles of physics-that is, had come to the study of organic matter in almost total ignorance of those laws which govern inorganic matter; had come to the investigation of the intricate machine, the human frame, without previously acquiring that knowledge which alone could enable them to understand even its simplest phenomena. It would have been amusing, had it not been painful, to observe the physiologist complacently persuading himself that in the study of living structures his mind was superior to the consideration of the principles of physic. Yet, while rapt in this conceit, he has been, from first to last, most eminently mechanical in his ideas of life, blundering on continually, and introducing explanations and expositions which are in accordance with no laws of physics, but are both mechanical and false. The details of the various experiments made to determine certain mechanical questions relating to the phenomena of the circulation, respiration, the movements and sounds of the heart, &c., are, with few exceptions, examples of an almost total want of such practical and well-digested knowledge of physical science as alone would enable the experimentalist to draw correct conclusions. These experiments, too, have almost all been unnecessary-no more required than the measuring a triangle by going over its whole surface inch by inch, instead of calculating by the one side and two angles given. It is, however, gratifying to perceive, that the certain sciences are more cultivated by the medical student than heretofore: they ought to form the groundwork of medical and surgical education: he who is well acquainted with them readily perceives how far they will apply to the various phenomena occurring in living beings, and it is he, and he alone, who gives no undue weight, no undue importance, to them. The result of their neglect has been, that of the whole mass of medical and surgical literature, nineteentwentieths are pure inanity, or worse-obstructions and stumblingblocks in the path of science. The intent of this paper is to explain familiarly that which Miiller could not understand-viz., absorption by lymphatics ' , and lacteals: an analysis of the phenomenon involves a consideration of I THE FORCES OF TIIE GENERAL CIRCULATION. There is one primary and essential source of motion to the I fluids of the human bodv-tlje heart: its influence is universal I , throughout the frame, and constant. ' , In addition to this primary and essential source of motion, , , there exist certain accessory forces, which are local in their influence, and are alternatelv assistant and obstructive, and ' i which result from the peristaltic action of the intestines, from I the movements of respiration, and from the exercise of the voluntary muscles. These forces are intrinsic, belonging to the machinery of the frame itself: but there is an extrinsic force, producing what is most improperly called absorption, and arising from those purely physical causes which occasion the phenomenon named solution. ' All the fluids of the circulation are passing from the heart, or passing towards it. The cavity of the heart, whence the blood departs, affords an example of the greatest pressure which the blood sustains; the cavity of the auricle, which receives fluid from all parts of the body, offers an example of the least pressure which those fluids sustain. The ventricle injects with fluid every vessel, cell, and cavity of the body, and if its compression of its contained fluid were not greater than that of any other vessel, cell, or cavity of the body, the circulation could not go on in such vessel, cell, or cavity. The auricle receives fluid from all parts of the body, and if the pressure were not less in the auricle than in any other vessel or cell of the body, their contained fluids could not return into its cavity. All the fluids of the circulation, in passing through their various channels from the cavity of the ventricle round to that of the auricle, are passing from the greatest pressure to the least. In passing from the heart, all fluids are passing from a greater pressure to a less; in passing to the heart, all fluids are passing from a greater pressure to a less. For elucidation, let the black lines of the following diagram represent the shortest circuit which the blood takes-namely, from the ventricle through the arteries, the capillaries, and the veins, into the auricle. The fluid leaves the ventricle (4) and enters the arteries, (3,) because the pressure is less in the arteries than in the ventricles; it leaves the arteries to enter the capillaries, (2,) because the pressure is less in those vessels than in the arteries ; from the capillaries (2) it passes into the veins, (1,) and from the veins it passes into the auricle, (0,) for the same reasons. The blood and other fluids do not move from a vital cause-they move because they are moved. The physiologist has perplexed himself by confounding vital and mechanical powers together. The blood, containing all the constituents of the body, is distributed, by the force of the ventricles, through the arteries, to all parts of the frame; it is received into the capillaries, where, in a state of minute division, it is brought under the influence of the nerves of organic life. In these vessels, according to the structure or mechanism of the organ supplied, a separation of certain constituents of the blood takes place-new combinations of its elements are formed. But the power which produces these changes is not what is called a mechanical power,-it is an atomic force, and does not affect the motion of the blood, considered as a mass. The fluid passes forward from the greater pressure to the less, until some local attraction arrests its atoms and fixes them, to add to, or to form, a tissue, and when these atoms are worn out, they fall into the current again. For further elucidation, let the dotted lines represent a longer course, and more minute vessels-say a vessel secreting lymph into a cell of the cellular tissue, with a lymphatic opening into the cell, and leading into the vena cava. In this case, a portion of the blood leaves the capillaries, and enters the cell. Now, the fluid enters this cell with a certain force; it distends this cell with a certain force; and as there exists a vessel leading to the right auricle, this same force induces the fluid to pass on towards the auricle that is to pass from a greater pressure to a less, with a current, slower than that of the shorter circuit, it is true, but still by the same mechanical force, that derived from the ventricle.