CALCAREOUS MANURES— PKACTICE, ^^j 



greater degree than to all others, that I attribute the beneficial effects 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 lime-stone, or rich indurated 

 clay marl. It was from these remarkable soils that the specimens were 

 obtained which were described at pp. 42, 43. 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 considera- 

 ble extent in the United States 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 formerly contained, and from 

 which they derived their peculiar and valuable qualities, may be supposed 

 only to be concealed by the accumulation of vegetable matter, according 

 to the general views submitted in chapter vii. The more full descriptions 

 of the soils of this remarkable and extensive region before referred to 

 render it unnecessary to enlarge much here. It will be sufficient to sum 

 up concisely the facts there exhibited — and which agree with various other 

 private accounts which have been received from undoubted sources of 

 information. The deductions from these facts, and their accordance with 

 the theory of the operation of calcareous 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, except the spots where the 

 soft lime-stone rises to the surface, and makes the calcareous ingredient 

 excessive. In the specimen formerly mentioned, the pure calcareous matter 

 formed 59 parts in the 100 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 intractablCj 

 that its tillage would be almost impracticable ; yet it is friable and light 

 when dry, and easy to till. But the superfluous rain water cannot sink 

 and pass off, as in sandy or other pervious lands, but is held in this close 

 and highly absorbent 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 and impervious marly substratum, deprive the country of natural 

 springs and running streams; and before the important discovery was 

 made that pure water might be obtained by boring from 300 to 700 feet 

 through the solid calcareous rock, the inhabitants used the stagnant rain 

 water collected in pits, which was very far from being either pure or pala- 

 table. Under all these circumstances, added to the rank herbage of 

 millions of acres annually dying and decomposing under a southern sun, 

 it might have been counted on, as almost certain, that such a country 

 would have proved very unhealthy. Yet the reverse is the fact, and in a 

 remarkable degree. The healthiness of this region is so connected with 

 and limited by the calcareous substratum and soil, that it could not escape 

 observation ; and they have been considered as cause and effect by those 

 who had no theory to support, and who did not spend a thought upon the 

 mode in which was produced the important result they so readily admitted. 

 Their testimony therefore is in this respect the more valuable, because it 

 cannot be suspected of having any such bias. 



To the time when this last publication is made, (1842,) there has been 

 no reason to doubt the actual facts of autumnal diseases (the effects of 

 malaria) being greatly lessened by even the partial use of marling ; nor 

 the inference that they would almost cease to occur, (if no mill-ponds and 

 undrained lands remained,) if all the surface of a considerable extent of 

 country were made calcareous, and all rapidly putrescent and otherwise 



