CALCAREOUS MANURES— PRACTICE. |3| 



is acid, the making it calcareous will enable half the usual supplies of 

 manure to be more effective and durable than the whole had been. There 

 are other uses for marl, about dwelling houses and in towns, which should 

 induce its being carried much farther than mere agricultural purposes 

 would warrant. I allude to the use of calcareous earth in preserving pu- 

 trescent matters, and thereby promoting cleanliness and health. This 

 important subject will hereafter be separately considered. 



Either lime or good marl may hereafter be profitably distributed over a 

 remote strip of poor land, by means of the rail-road now constructing from 

 Petersburg to the Roanoke [1831]; provided the proprietors do not imitate 

 the over greedy policy of the legislature of Virginia in imposing tolls on 

 manures passing through the James river canal. If there were no object 

 whatever in view but to draw the greatest possible income from tolls on 

 canals and roads, true policy would direct that all manures should pass 

 from town to country toll free. Every bushel of lime, marl, or gypsum 

 thus conveyed, would be the means of bringing back, in future time, more 

 than as much wheat or corn; and there would be an actual gain in tolls, 

 besides the twenty-fold greater increase to the wealth of individuals and 

 the state. Wood-ashes, after being deprived of their potash, have calca- 

 reous earth, and a smaller proportion of phosphate of lime, as their only 

 fertilizing ingredients ; and both together do not commonly make more 

 than there is of calcareous earth in the same bulk of good marl. Yet 

 drawn ashes have been purchased largely from our soap factories, at five 

 cents the bushel, and carried by sea to be sold for manure to the farmers of 

 Long Island. Except for the proportion of phosphate of lime which they 

 contain, drawn ashes are simply artificial marl— more fit for immediate 

 action, by being finely divided, but weaker in amount of calcareous earth 

 than our best beds of fossil shells. 



The argument in support of the several propositions which have been 

 discussed through so many chapters, is now concluded. However un- 

 skilfully, I flatter myself that it has been effectually used ; and that the 

 general deficiency in our soils of calcareous earth, the necessity of supply- 

 ing it, the profit by that means to be derived, and the high importance of 

 all these considerations, have been established too firmly to be shaken by 

 either arguments or facts. 



CHAPTER XIV. 



ESTIMATES OF THE COST OF LABOR APPLIED TO MARLING. 



Before we can estimate with any truth the expense of improving land 

 by marling, it is necessary to fix the fair cost of every kind of labor ne- 

 cessary for the purpose, and for a length of time not less than one year. 

 We very often hear guesses of how much a day's labor of a man, a horse, 

 or a wagon and team, may be worth— and all are wide of the truth, be- 

 cause they are made on wrong premises, or no premises whatever. The 

 only correct method is to reduce every kind of labor to its elements — and 

 to fix the cost of every particular necessary to furnish it. This I shall 

 attempt ; and if my estimates are erroneous in any particular, other persons 

 better informed may easily correct my calculation in that respect, and make 

 the necessary allowance on the final amount. Thus, even my mistakes in 



