303 



other refuse matters, and of marl or lime. With the latter, the vegeta- 

 ble substance of peat enters into new combinations, forming certain 

 soluble salts, which are then ready to be taken up as food by plants. 



We have already seen how frequently peat and marl ai-e found in 

 connection, and in what abundance the latter may be procured. In 

 peat and marl combined, we have, therefore, all that could be required, 

 to make of those numerous marshes which intersect the country, im- 

 mense receptacles of vegetable nutriment. The lime performs to the 

 mass of raw organic matter of the peat, the office which the cook does 

 to the larder. Conjoined, they furnish both provision for the nourish- 

 ment of plants, and the means for preparing it. 



Some contrariety of opinion exists on the use of calcareous manures, 

 (gypsum and limes,) from the supposition that they eventually wear out 

 the land, leaving it poorer than before. Now such a result may hap- 

 pen from either of two causes, neither of which implies any injurious 

 quality in the mineral : 



1st. From the too excessive use of this manure, or its application to 

 soils, the composition of which was not understood, and where lime 

 may already have formed an abundant element. 



2d. From the use of mineral manures solely, under the mistaken 

 supposition that they furnish the necessary nutriment to vegetation. 

 Now, as has just been shown, these chiefly serve to prepare the food 

 which has been furnished from other sources. So far from supplying 

 the place of vegetable and animal manures, they only render necessary 

 fresh supplies of the latter. By giving increased activity to vegetation, 

 they of coui-se cause a quicker consumption of the fertilizing principles. 

 It will thus very easily be seen from what mistaken practice this " im- 

 poverishing of the soil," by the use of mineral manures, results, and 

 also where may be found the proper corrective. 



BOG IRON ORE, AND OCHRE. 



All our bog ores are a product of the diluvial or alluvial deposits, the 

 mineral being originally contained in the feiTuginous sands or clays. It 

 is taken up in solution by rain-waters, and afterwards, Uke the marls, 

 deposited in low grounds. 



Sands highly ferruginous, and beds of sandy ochre, of a bright red 

 or yellow color, are not uncommon, though in general of small extent. 

 Some considerable beds were observed in Lenawee county, ranged along 



