158 



FxlRMERS REGISTER. 



[No. S 



3'eous earth; and the remarkable charifre from un- 

 healthines-'s in Mobile, to comparative healthiness, 

 is a very strong exemplification of the truth of 

 the theory. But it is not strange, that when so 

 many other causes might (and probably did) ope- 

 rate to arrest diseases, that none should have con- 

 sidered the chemical operation of the shelly pave- 

 ment as o;ie of them, and slill less as the one by 

 far the most important. The paving: of streets, 

 (with any material,) draininji and lilling up wet 

 places, substilutino- jbr rotting Avooden building's 

 new ones of brick and stone — and especially the 

 operation of destructive and extensive fires — all 

 operate wc know, (and particularly tlie last,) to 

 improve the healthiness of ton'ns; and all these 

 •operated at Moliile, as well as shelliiif}; the streets. 

 Neither was the shellinsi; so ordered as to pro- 

 duce its best etlect for health. The streets, alleys, 

 arnl many yards and small vacant lots were cover- 

 ed, and so lar the Ibrmation and evolving of pes- 

 tilential efnuvia were lessened. l>ut as ihis was 

 not the object in view, and indeed the chemical 

 action of shells was not thought ojj the process 

 was incomplete, and must necessarily be less ef- 

 fectual than it might have been made. The 

 shelling ought to have been extended to every 

 open spot where fillh could accumulate — to every 

 back yard, to every cellar, and made the material 

 of the floor of every stable, and of all other build- 

 ings of which the floor would otherwise be of com- 

 mon earth. In addition, afler a sufficient lapse 

 of time to saturate with putrescent matters the 

 upper part of the calcareous layer, and thus to 

 make it a very rich compound, there should be a 

 partial or total removal of the mass, and a new 

 coaung of shells laid down. The value of the 

 old material, as manure, would probably go lar 

 towards paying lor this renewal: and if it is not 

 so renewed, the calcareous matter cannot com- 

 bine with more than a certain amount of putres- 

 cent matters — and after being so saturated, can 

 have no farther effect in saving such matters tor 

 use, or preventing them from having their usual 

 evil course. 



The burning of towns is well known to be a 

 cause of the healthiness of the places being great- 

 ly improved, and that that effect continues after as 

 many buildings, or more, have replaced those des- 

 troyed by fire. Indeed this improvement is con- 

 sidered so permanent, as well as considerable, 

 that the most sweeping and destructive conflaixra- 

 tions of some of our southern towns, have been 

 aiierwards acknowledged to have proved a gain, 

 and a blessing. The principal and immediate 

 mode of operation of this universally aclcnow- 

 ledged cause, is usually supposed to be the total 

 destruction, by the fire, of all filth and putrescent 

 matters — and in a less degree, and more gradually, 

 by afterwards substituting brick and stone for 

 wooden buildings, which are always in a more or 

 les.s decaying state. But though these reasons 

 have served heretofore to satisfy all, as to the be- 

 neficial consequences of fires, surely they are alto- 

 gether inadequate as causes for such great and 

 durable effects. Tlie mere destruction ot' all pu- 

 trescent matters in a town, at any one time, would 

 certainly leave a clear atmosphere, and give 

 strong assurance of health being improved for a 

 short time afterwards: but these matters would be 

 replaced, probably in the course of few months, 

 by the residence of as many inhabitants, and the 



continuance of the same general habits — and most 

 certainly this cause would lose all its operation by 

 the time the town was rebuilt. But there is one 

 operation produced by the burning of a town, 

 which is far more powerful — which in fact is indi- 

 rectly the very practice which has been advocated 

 — and the effect of which, if given its due weight, 

 furnishes proof of the theory set forth, by the ex- 

 perience of every unhealthy town which has suf- 

 iiired much from fire. If any estimate is made of 

 the immense quantity of mild calcareous earth 

 which is contained in the plastering and brick- 

 work of even the wooden dwelling houses of a 

 town, (and still more of those built of masonry) 

 it must be admitted that all that material being 

 separated, broken down, and (soon or late,) s[)read 

 by the burning of the houses and pulling down of 

 their ruins, is enough to give a very heavy cover 

 of calcareous earth to the whole space of land 

 burnt over. It is to this operation, in a far greater 

 degree than to all others, that I attribute the bene- 

 ficial e0(3cls to health of the burning of towns. 



I proceed to the facts derived from the extensive 

 body of prairie lands in Alabama which rest on 

 a substratum of soft limestone, or rich indurated 

 clay marl. It was fi'om these remarkable soils 

 that the specimens were obtained which were de- 

 scribed at page 22. Some of these, indeed all 

 that have been examined by chemical tests of the 

 high and dry prairie lands, contain calcareous 

 earth in larger proportions than any soils of con- 

 siderable extent in the United Slates that I have 

 seen, or tested. The specimens not containing' 

 free calcareous earth are of the class of" neutral 

 soils; and the calcareous earth, which doubtless 

 they Ibrmerly contained, and from which they de- 

 rived their peculiar and valuable (^jalities, may be 

 supposed only to be concealed by the accumula- 

 tion of vegetable matter, according to the general 

 views submitted in chapter vii. The more full 

 descriptions of the soils of this remarkable and ex- 

 tensive region which will be placed in the Appen- 

 dix [at N] render it unnecessary to enlarge much 

 here. It will be sufficient to sum up concisely the 

 facts there exhibited — and which agree with va- 

 rious other private accounts which liave been re- 

 ceived from undoubted sources of information. 

 The deductions from these facts, and their accord- 

 ance with the theory of the operation of calcare- 

 ous matter, are matters of reasoning, and as such, 

 are submitted to the consideration and judgment 

 of readers. 



The soil of these prairie lands is very rich, ex- 

 cept the spots where the soft limestone rises to 

 the surface, and makes the calcareous ingredient 

 excessive: in the specimen formerly mentioned, 

 the pure calcareous matter formed 59 parts in the 

 hundred of this "bald prairie" land. The soil 

 generally has so little of sand, that nothing but 

 the calcareous matter, which enters so largely into 

 its composition, prevents it being so stiff' and in- 

 tractable, that its tillage would be almost impracti- 

 cable; j^et it is friable and light when dry, and 

 easy to till. But the superfluous rain water can- 

 not sink and pass off, as in sandy or other pervious 

 lands, but is held in this close and highly absor- 

 bent soil, which throughout winter is thereby 

 made a deep mire, unfit to prepare for tillage, and 

 scarcely practicable to travel over. This water- 

 holding quality of the soil, and the nearness to the 

 surface of the hard marly substratum, deprive the 



