"It may be proper here to apologize for many of the subsequent conjectures on some articles of natural philosophy, as not being supported by accurate investigation or conclusive experiments. Extravagant theories however in those parts of philosophy, where our knowledge is yet imperfect, are not without their use; as they encourage the execution of laborious experiments, or the investigation of ingenious deductions, to confirm or refute them. "

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Product Description: This collection of literature attempts to compile many of the classic, timeless works that have stood the test of time and offer them at a reduced, affordable price, in an attractive volume so that everyone can enjoy them.

The irritability of the whole, or of part, of our system is perpetually changing; these vicissitudes of irritability and of inirritability are believed to depend on the accumulation or exhaustion of the sensorial power, as their proximate cause; and on the difference of the present stimulus, and of that which we had previously been accustomed to, as their remote cause. Thus a smaller degree of heat produces pain and inflammation in our hands, after they have been for a time immersed in snow; which is owing to the accumulation of sensorial power in the moving fibres of the cutaneous vessels during their previous quiescence, when they were benumbed with cold. And we feel ourselves cold in the usual temperature of the atmosphere on coming out of a warm room; which is owing to the exhaustion of sensorial power in the moving fibres of the vessels of the skin by their previous increased activity, into which they were excited by unusual heat. Hence the cold fits of fever are the occasion of the succeeding hot ones; and the hot fits contribute to occasion in their turn the succeeding cold ones. And though the increase of stimulus, as of heat, exercise, or distention, will produce an increased action of the stimulated fibres; in the same manner as it is produced by the increased irritability which was occasioned by a previous defect of stimulus; yet as the excesses of irritation from the stimulus of external things are more easily avoided than the deficiencies of it; the diseases of this country, except those which are the consequences of drunkenness, or of immoderate exercise, more frequently begin with torpor than with orgasm; that is, with inactivity of some parts, or of the whole of the system, and consequent coldness, than with increased activity, and consequent heat. If the hot fit be the consequence of the cold one, it may be asked if they are proportionate to each other: it is probable that they are, where no part is destroyed by the cold fit, as in mortification or death. But we have no measure to distinguish this, except the time of their duration; whereas the extent of the torpor over a greater or less part of the system, which occasions the cold fit; or of the exertion which occasions the hot one; as well as the degree of such torpor or exertion, are perhaps more material than the time of their duration. Besides this some muscles are less liable to accumulate sensorial power during their torpor, than others, as the locomotive muscles compared with the capillary arteries; on all which accounts a long cold fit may often be followed by a short hot one.

Product Description: Erasmus Darwin has often been cited as the most widely talented man of the past 250 years. He excelled in medicine and poetry, was an inventor and wide ranging man of science, and founded several societies. This 2006 collection of 460 of his letters provides an insight into the life of this amazing man...read more

Product Description: Erasmus Darwin (1731-1802) is remembered not only as the grandfather of Charles but as a pioneering scientist in his own right. A friend and correspondent of Josiah Wedgwood, Joseph Priestley and Matthew Boulton, he practised medicine in Lichfield, but also wrote prolifically on scientific subjects...read more

Product Description: This scarce antiquarian book is a facsimile reprint of the original. Due to its age, it may contain imperfections such as marks, notations, marginalia and flawed pages. Because we believe this work is culturally important, we have made it available as part of our commitment for protecting, preserving, and promoting the world's literature in affordable, high quality, modern editions that are true to the original work...read more

Product Description: Erasmus Darwin (1731-1802) was an accomplished scientist and inventor, one of the most successful doctors in eighteenth-century England, and a best-selling poet. He anticipated a theory of biological evolution a full 70 years before his grandson Charles's On the Origin of Species, and his poetry had a marked influence on Wordsworth and other Romantics...read more

Product Description: This scarce antiquarian book is a facsimile reprint of the original. Due to its age, it may contain imperfections such as marks, notations, marginalia and flawed pages. Because we believe this work is culturally important, we have made it available as part of our commitment for protecting, preserving, and promoting the world's literature in affordable, high quality, modern editions that are true to the original work...read more

Product Description: Erasmus Darwin has often been cited as the most widely talented man of the past 250 years. He excelled in medicine and poetry, was an inventor and wide ranging man of science, and founded several societies. This 2006 collection of 460 of his letters provides an insight into the life of this amazing man...read more