Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.

21. Men, in like manner, may be saved in towns, camps, and houses, from being made the vehicles of currents which are quite capable of deranging the mechanical order, the chemical action, and the physical function, of every atom and organ of the human body. 22. That " marsh miasm" is a misnomer, and a weak invention to cover want of knowledge —a ''mysterious emanation," supposed to arise like a spirit from the fenny deep, and to infect air, soil, and water —a pestilential something, reputed to be malaria itself. But no chemist has yet separated this germ of evil from the marshes in which it is thought to be engendered. 23. That early in life, a believer in these misty delusions of marsh poison, I did hope that improved tests and apparatus would arrest the " gas," and de- tect its composition. But continued trials, during twenty years, all failed to render it tangible. As yet, there has been no analysis of this "pest," although its sway is dreaded alike in the lowest valleys and on the highest hills. 24. That no doctrine can be more mischievous than this of " miasms;" for if there be such a poison, sui generis, wafted about in the air we breathe, there can be no precaution by which we may hope to ward off such an enemy while it continues unknown and unseen. 25. That no harm can result from any attempts to overturn the faith that was in us, and to believe in some other power capable in various ways of being felt, seen, heard, or understood. If, therefore, we come to ascertain that elec- tricity at rest, or electricity in motion, or that some of its modifications, — gal- vanism or magnetism,—can induce a hroken balance of electrical equivalents in animals, we may more easily devise means of warding off a known power, and preventing its transit through the conducting materials of living beings. 26. That while the relations of electrical influence to the laws of life are universally admitted, the very existence of marsh miasms may be well denied. An able writer observes that " their nature is not known ; neither their physi- cal nor their chemical properties have been ascertained. Even their presence is known only by their effects on the human constitution ; no other test of their existence has yet been discovered. Some conjecture, that this poisonous gas is carbonic acid; others, that it is azote and oxygen; but chemistry has yet to discover whether this poison be simple or compound, as well as by what test, other than its action on the human body, its presence may be determined." 27. Were miasms of ponds and fens, of drains, sewers, and swamps, the exciting cause of cholera or agues, this pestilence, wafted in the fleeting winds, would be just as variable in its effects as the wind itself. We should then have every possible shade of suffering, but no parallel epidemics. Every variety of inhaled poisoning would prevail at the same time and place. But, on the contrary, intermittents and all symmetrical diseases, induced by sym- metrical causes, are similar in character, and no two of them prevail in the same place and at the same time. Definite causes produce definite effects; and it was justly observed, in the late sanitary reports, " that cholera and