Popular Science Monthly Volume 24 January 1884 The Source Of Muscular Energy

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By J. M. STILLMAN, Ph. NEW and valuable scientific discoveries and inventions usually are not sluggish at the present time in making their way from the closets and laboratories of the investigators or discoverers to popular recognition. It's considerably in any other case with the gradual growth of knowledge on topics once thought to have been tolerably clearly understood and of no immediate practical worth. The gradual modifications which happen in usually accepted theories by the slowly accumulating outcomes of the labor of many investigators are, to make certain, appreciated by the particular student in the particular division of data involved, however are slower in assembly with public recognition. It thus occurs that teachers and books, not dealing as a specialty with the subject involved, often adopt and repeat as authoritative views and theories which, by the specialists in those branches, have either been abandoned or brought severely into question. Nor is it to be in any other case anticipated.



Chroniclers are fast to seize upon and distribute the information of sensible or startling discoveries or innovations, however those are fewer who will track patiently the slowly accumulating evidence of many employees, appreciate the bearing of their work, and produce it in a form during which it may be appreciated by these non-specialists most interested by the subject involved. It is thus, to a certain extent, with the subject of the supply of muscular energy within the animal organism. It's pointless to specify on this particular. Text-books and well-liked articles touching on the subject are regularly asserting, as apparently unquestioned, theories which at the present time are either exploded or very a lot in doubt. It would appear, due to this fact, not without worth to try, so far as practicable in a preferred or semi-widespread article, a general statement of the present condition of the theories on the source of muscular energy, and of the primary factors of the evidence which tends to help these theories.



The general acceptance of the law of the conservation and correlation of physical forces had at once an vital influence in directing attention to the source of muscular pressure. The thought was readily taken up that this form of power is on the expense of heat, which is produced by the oxidation of carbon and hydrogen in the physique, the mandatory oxygen being conveyed by the arterial blood to the muscular tissue. In different words, the somewhat trite comparability of the human physique and the muscular system to an engine, which consumes simply so much gas to provide so much pressure, has pretty clearly formulated the concept as typically accepted. And to date because it goes the comparability just isn't unhealthy. When, nevertheless, we go past this considerably obscure simile to an examination of the extra intimate nature of these varied processes, we discover the questions raised should not so typically understood.



Accepting that the muscular force is produced by the final word oxidation of carbon and hydrogen to carbonic-acid gasoline and water respectively, the next questions that recommend themselves are: "What's the immediate supply of this carbon and hydrogen-the fuel materials for muscular drive?" and "What is the actual nature of these processes which we call briefly oxidation?" The endeavors to answer these questions have given rise to many discussions and disputes, that are, even at the present day, on no account concluded. Before taking on the dialogue of the theories advanced to answer these questions, it won't be out of place to evaluate very briefly the composition of the muscles and their normal relations to the circulation-only in to this point, nevertheless, as is necessary for a transparent comprehension of the evidence and arguments concerned in the discussion. A muscle is basically a group of lengthened cells held collectively by a connective tissue. Each cell consists of a delicate cell-wall or membrane containing a fluid or semi-fluid mass of residing (protoplasmic) matter.



This gelatinous substance possesses the power of contraction underneath the stimulus of excitations of assorted kinds-nervous impulse, electricity, heat-and the cell becomes thereby shortened. This process, going down simultaneously in all of the cells of a given muscle below the affect of the same exciting trigger, is what exerts the power of the contracting muscle. The intensity of this shortening or contracting power has been approximately measured-e. The muscles are equipped with blood by the positive ramifications of the arteries, and the blood is performed away again by the ramifications of the veins, the arterial blood shedding oxygen and taking up carbonic acid throughout its passage, as is the case in the other tissues additionally. Regarding the composition of the muscular tissue, it may be simply famous that the tissue itself is composed primarily of albuminoid material (cell-contents) and of the substance of the connective tissue, which is, just like the albuminoids, composed mainly of carbon, BloodVitals home monitor hydrogen, oxygen, BloodVitals home monitor and nitrogen, and in much the identical proportions.