1839] 



FARMERS' REGISTER 



293 



mance, and entirely within the capacity oi" the 

 most ordinary persons. Litiit! children readily 

 coinprehenil, and can perform tiic whole, alter 

 once practisinif it ; and they would never require 

 adult supervision, but for iheir liability to nroii- 

 gence. AH capacities are capable oi' performing, 

 but lew of direct ini^ the work. The art of silk- 

 niakiiiff, ihoutjli simple and easily acquired in all 

 its parts, requires the strictest attention, that every 

 act, thuu<rh extremely simple in itself, be done at 

 the proper time, and in the proper manner. 



Malaria — its effects in producing coun- 

 try AN» OTHER FEVERS. 



From the Southern Agriculturist. 



3Ir. Editor — Believing that the followinfif re- 

 marks on the laws which govern the production 

 and propagation of malaria, may in a measure be 

 useful and mteresting to many of your readers, 

 (i-otn the fact of the prevalence and fatality of what 

 is termed country tever amongst our inhabitants, 

 and especially the agricultural portion, I have been 

 induced to submit them to you lor your journal, if 

 you think them worthy of a place in its pages. I 

 have condensed the subject very much, from llie 

 circumstance of the limitof a journal like this, and 

 have only detailed some very striking liicts which 

 cannot fail to be interesting. 



The first law we shall notice in regard to the 

 propagation of malaria, is that it obeys the motion 

 of the atmosphere, being conveyed by winds to 

 some distance from the locality where it is gener- 

 ated, with equal if not greater latality. Ithasoften 

 been attempted to ascertain the precise or proba- 

 ble distance that malaria can be conveyed by 

 winds, to produce fever; but all such attempts 

 have tailed to establish any exact or certain dis- 

 tance. Notwithstanding this, cases are related 

 where it has been transmitted to the distance of 

 even three miles. The convent of Camaldoli, in 

 Italy, is an illustration of this fact. It is situated 

 on a very high hill, three miles from the lake 

 Agnano, which is the nearest source of mala- 

 ria, producing remittent and intermittent fevers 

 amongst the inmates. We are inlbrmed by a 

 writer on the climate of Italy, that out of seventy- 

 six unhealthy towns and villages, thirty-five are 

 situated on hills some distance tiom the locality like- 

 ly to produce malaria. The marshes about Kreth 

 in Kent, says M'Culloch, are less injurious to the 

 inhabitants of the lower grounds near them, than 

 might be expected, while their eifects on the houses 

 which are situated high on the hills above, is 

 such as at different times to have been severely 

 felt by the inhabitants. This circumstance he attri- 

 ribuies to a current of air so directed, as to escape 

 the low grounds, while it ascends and atlecls the 

 eminences. 



The distance at which malaria may produce its 

 effects, constitutes a subject worthy of inquiry; 

 for individuals living in the country often think the 

 location of their residence sale, because they have 

 no standing water near them, when tliere is a 

 Bwamp, or a low piece of ground some distance ofi'. 

 When lijver prevails, they seldom or never think 

 or believe, that the exciting cause may be only a 

 mile or two miles off; but they imagine the sick- 

 ness to be of a peculiar nature, qot in any way 



attributable to -the immediate locality. These 

 hints may prove useful to many of my readers in 

 the choice of their summer residences, which 

 ought to be a lew miles from any locality to gene- 

 rate malaria. 



Writers on the diseases of warm climates have 

 slated many liicts in relation to this part of our 

 subject, which are highly interesting and impor- 

 tant. Some of these authors do not th'nk that this 

 poison can produce disease at the distance of more 

 than a quarter of a mile. Dr. Lind, in his observa- 

 tions on the preservation of the healih of seamen, 

 says, "that when Commodore Jjong's squadron, 

 in the months of July and August, in 1744, lay of!' 

 the mouih of the Tiber, it was otiserved that one 

 or two of the ships which lay closest to the shore, 

 began to he affected by the pernicious vapor from 

 the land, whilst some lying further out at sea, 

 at but a very small distance from the Ibrrner, had 

 not a man sick. At the same time, the Austrian 

 army, under the command of Prince Lobcowitz, 

 sufiereii so great sickness, through the proximity of 

 their situation to the marshy country, that they 

 were obliged to decamp." There is no doubt that 

 the distance to which malaria may be conveyed, 

 depends much upon the wind, which when strong, 

 many waft this poison many miles. Dr. Bancroft, 

 in his work on yellow fever, expresses himself 

 strongly on this subject. "The distance, says he, 

 to which the exhalations of marshy grounds may 

 be convened from their source, and retain the 

 poison of causing the yellow or other maivh lever, 

 will partly depend on the force of the wind, ami 

 partly on the extent of the surlace from which they 

 arise — and on their being more or less copiously ex- 

 tricated fi-om that surface. If the vvind be very mo- 

 derate, and blow steadily from the same point, and 

 if the miasmata be abundantly emitted from a very 

 great extent of surljjce, it seems probable that so 

 large a mass of them as would thus be formed,, 

 might be conveyed a quarter and perhaps a half 

 nnle, belbre it became so diluted wuh atmospheric 

 air, or so dissipated by the wind, as to lose its 

 morbific power." This is only supposition on the 

 part of this author ; but the case cited before of the 

 convent of Camaldoli, proves that it has been 

 known to produce its deadly effect at the distance of* 

 three miles. A very strikinii instance of the action 

 of the winds in conveying malaria, is o-iven by Lan- 

 cisi. Thirty persons of distinction in Rome having 

 been on a party of pleasure towards the mouth ol' 

 the Tiber, the wind shifted suddenly to the south- 

 ward, blowing over some inlectious marshes, and 

 in a very short time twenty-nine of the party were 

 attacked by Itjver. 



Another i^nportant law in relation to malaria is, 

 that it is dispersed by the the rays of the sun, for 

 which reason the nights and the early niorning 

 are the most dangerous times to be exposed to 

 miasmatic districts. The fog or vapor, when ac- 

 ted upon by the heat of the sun, is ratified, and 

 becoming lighter than the surrounding atmosphere, 

 ascends to some considerable height. By this pro- 

 cess, the sickness on high mountains has been 

 accounted for. Individuals exposed at night to 

 malaria, have imitated this law of nature, by 

 building up large fires, the heat of which has the 

 same chemical effect as that of tlie sun. The 

 use of fires in dissipating malaria, and rendering 

 it innoxious has been long known and acted upon. 

 We have the authority of Lancisi, Pliny and 



