516 



THE SOUTHERN PLANTER. [September 



Marl Irom the State of Delaware, ac- 

 cording to Mr. Booth, does not differ very 

 much from that of New Jersey. But in Dela- 

 ware there are two varieties, proximate one to 

 the other, and one of which contains as high 

 as 25 per cent, of carbonate of lime. Mons. 

 P. Berthier, professor of Docimacie, in the 

 royal school of mines, of France, has an- 

 alyzed several varieties, which are more or 

 less analogous in composition to the green 

 sand of New Jersey. The bluffs called 

 Cape La II eve, near Havre, in France, are 

 mainly formed of carbonate of lime, through 

 which are interspersed noduhs and grains 

 of a dark-greenish substance, which yielded : 



Silica, . 



50.00 



Protoxyd of iron, 



. 21.00 



Magnesia, . 



7.00 



Alumina, 



. 11.00 



Potassa, 



10.00 





99.00 







The grains of chlorite are found isolated 

 and distinct in the limestone at Havre. 

 Analysis represents the composition of those 

 grains free from the mass in which they 

 occur. The analysis of Mr. Seybert ex- 

 hibits, as I have understood, the average of 

 the deposit as it came from the ground. 

 If it be otherwise, and the particles of 

 chlorite were selected previous to' analysis, 

 the green sand of New Jersey would be in- 

 finitely less valuable as a fertilizer than is 

 indicated by the above analysis. In other 

 parts of the United States, other substances 

 of an entirely different composition have 

 received the name of marl, and been ap- 

 plied to the soil with marked advantage. 

 Such a substance is found in the environs 

 Of Pendleton, in South Carolina, where it 

 has attracted attention. It is a variety of 

 kaolin, or decomposed feldspar, one of the 

 constituents of granite, containing little or 

 no lime, bnt sometimes as high as 17 per 

 cent, of potassa. At Fort Hill, the resi- 

 dence of the late J. C. Calhoun, this sub- 

 stance was found in digging a well. It was 

 used in dressing the lawn in front of the 

 dwelling, where its fertilizing effects are 

 manifest to this day in a luxuriant sward, 

 contrasting vividly with the surrounding 

 vegetation on which the application was 

 not made. In 1837, some years , after the 

 experiment, it was pointed out by Mi. Cal- 

 houn as an illustration of the adaptability 



| of that country to produce luxuriant grass; 

 j if the soil were properly treated. 



We speak of marl as always containing 

 the calcareous principle, in whieh sand, 

 clay, or carbonate of lime may predomi- 

 nate, it accordingly receiving the appella- 

 tion of sandy or clay marl, as either princi- 

 ple may be in excess. Few marls are free 

 from admixture with the above named sub- 

 stances, and sometimes others are found, 

 such as oxyd of iron, sulphuret of iron, 

 manganese, sulphate of lime, &c. The ma- 

 jority of our soils cast of the mountains, 

 originate from the old granitic schistose and 

 sandstone rocks, which are wanting in the 

 proper proportions of lime to make them 

 as fertile as those soils having a different 

 origin. Animals fed on the grass grown 

 upon limestone land, or those artificially 

 limed, thrive much better than when pas- 

 tured upon lands of a different character. 

 It is also known that wheat weighs heavier, 

 has a much better appearance, and is in- 

 variably preferred by millers when grown 

 upon calcareous soils. It is, then, of impor- 

 tance to the agriculturist that he should pos- 

 sess a knowledge of the presence or absence 

 of lime in his soil, and how to make 

 examinations, both qualitative and quanti- 

 tative, for that substance or minerals sup- 

 posed to contain carbonate of lime. 



No mineral varies more in its physical 

 character than marl. It occurs of all col- 

 ours, from black to white; and frequently 

 in the same bed you have a variety of 

 tones, as there may be present more or 

 less oxyd of iron ; or according to the state 

 of oxydation of that metal, you may have 

 the red, yellow, brown, bine, and the dif- 

 ferent shades which a mixture of these 

 would create when variously mixed with 

 white, black, &c. Sometimes it is smooth 

 and without grit; at others it has a coarse 

 grain, with crystals of other mineral sub- 

 stances disseminated, such as sulphate of 

 lime and quartz. Chalk is a marl, through 

 which nodules of flint occur, sometimes in 

 large quantities, and sometimes the carbo- 

 nate of lime disappears altogether, and is 

 replaced by silicious matter. Very often 

 the bed may be wholly composed of shells, 

 broken or entire, or even visible to the 

 naked eye, but revealing through the mi- 

 croscope the remains of minute organisms 

 forming the complete mass. It is some- 

 times soft and unctuous to the touch, friable, 

 or hard. But it has one general property, 



