316 AGRICULTURAL REPORT. 



The^'G three tilings in combination are the great agents for the production of 

 miasm : no two of th^-ra can produce it. They all must be present together, 

 and for a consid.rable time, so as to produce de,structive decay of the vegeta- 

 tion, whii-h requires a di^gree of heat exceeding eighty degrees Fahrenheit. 

 Thest' three eh-ments will always produce mia.^m, whether out of doors, under 

 the influence' of the heat of the sun, or on shipboard, or in an uncleanly kitchen, 

 by the heat of stuvos or fireplaces. 



If, then, a farmer builds his house over a " filling," he will have sickness in 

 his household. If he builds on "bottom lands," "made land," where running 

 stream-; have in the course of years been depositing decaying and dead leaves, 

 mud, &;c., h<' will ci^rtaiHly have various diseases in his family, unless a system 

 of th' -rough and constant draining is put in operation. 



Ponds, sluggish strrams, or any accumulations of water in a productive soil, 

 always yield miasm,, and a dwelling in their vicinity will be certainly visited 

 with miasmatic diseases, unless attention is paid to certain circumstances which 

 may modify the result. 



Miasm is not supposed to pass a swift-ninning stream ; hence if a stream 

 runs throiTgh a farm, and one bank of it is level and rich, the other higher and 

 rolling, better far build on the latter, for then the miasm of the flat land cannot 

 cross the stream to the house. If there is no stream, but a pond or flat land, 

 and the house must be built in the vicinity, build it so that the prevailing 

 winds from June to October shall blow from the house toward the pond or flat 

 land, i'or miasm, being a gas or air, is carried before the wind. 



It is a hazardous experiment to build on an eminence, if it gradually slopes 

 to the water's edge, or to a low, flat piece of ground, unless there is a growth 

 of trees or other shrubbery intervening, because miasm, like the clouds, will 

 sometimes "roll up" the side of a hill or mountain. It is known that vigorous 

 growing bushes, or hedges, or trees, between a miasm-producing locality and a 

 dwelling, antagonize the miasmatic influences, the living leaves seeming to 

 absorb and foed u2")on the miasm ; but there should be a space of fifty yards at 

 least between the hedge and the house, and the thicker and broader and higher 

 tlic hedge the better, and the nearer the leaves are to the ground the b^ter; for 

 the miasm gropes on the surface in its greatest malignity, and is seldom con- 

 e<ntrated enough at the height of ten feet to be materially hurtful to man, 

 unless it comes up a slope. Hence in the old cities of the world, in the times 

 of plagues and pestilences, the people who could not "go to the countiy" had 

 a custom among them to live in the upper stories of their dwellings while the 

 sickness raged. They would not even come down stairs to obtain marketing, 

 but would let down baskets by ropes to the country people for the provisions 

 they had to sell. But they failed to discover why the country people could 

 come to town with impunity, while they themselves were safe from disease ia 

 proportion as they lived in the upper stories of their dwellings. But a law of 

 miasm has since been determined, which beautifully unravels the mystery. 

 Miasm is condtnsed by cold, made heavy, and falls to the earth, hovering, as 

 it were, within a foot of its surface ; hence is not breathed, unless a man sleeps 

 OCD the ground. On the other hand, heat so rarefies miasm as to mako it com- 

 paratively innocuous. Hence the coolness of the early morning and of sun- 

 down throw the miasm to the surface by condensing or concentrating it, and 

 thus making it heav}- ; while the heat of the day of a summer's sun so rarefied 

 and lightened tlie miasm as to send it upward to the clouds. The country 

 people came to town in the daytime ! 



Less than fifty years ago the yellow fever and other deadly diseases prevailed 

 in Charleston, South Carolina, and it was known to be certain death, except to 

 the very hardy or the acclimated, to sleep in the city a single night ; yet the merr 

 cliants came to town at midday, under a blistering July sun, with perfect 

 impunity. Hence, from June to October, it is best for farmers' families to 



