NORTH-OAEOLINA GEOLOGICAL SURVEY. 103 



Carbonate of lime, 71.22 



99.62 



The sand is in the form of white grains, often coarse. It is 

 a soft, earthy marl, and is made up of fragments of corals, 

 shells, crinoid's or pentacrinites, with sand mechanically mixed. 



The influence of this marl upon vegetation has always been 

 favorable, and the testimony of Mr. Wadsworth, whose ample 

 experience qualifies him to advance an opinion, fully sustains 

 the foregoing statement. 



I subjoin an interesting letter from Mr. Wadsworth upon 

 the subject of marl and marling. His observations, I have 

 no doubt, will be concurred in by his neighbors. I am the 

 more desirous of making his letter public on account of his 

 experiment with marl upon his premises for the purpose of 

 counteracting the tendency to fever and ague during the au- 

 tumnal months. If farther trial should confirm the opinion 

 expressed in favor of the use of marl as a preventive of 

 fever, the importance of the discovery cannot be over-esti- 

 mated : 



CORE CREEK, GRAVEN COUNTY, ) 

 May TO, 1857. \ 



PROF. E. EMMONS Sir: The marl, (a specimen of which is sent,) I 

 have been applying since 1852. I have now marled 220 acres. I have, 

 until this year and a portion of the last, applied 100 bushels to the acre. 

 I am now using 75. The weaker parts of my land were burned with the 

 former quantity. My land varies from a very stiff clay to a soil quite light. 

 Presuming you will be willing to be troubled with it, I will give you my 

 mode of using it, and the results: My carts are made to 'hold just five 

 bushels. I have the land checked off with the plough into as many squares 

 to the acre as I design putting on bushels of marl. One bushel is put into 

 each square. The first four bushels is pulled out with a hoe from the tail 

 of the cart, and the last one is dumped. 



By this method I am enabled to have the material much more equally 

 spread, which I think is a full equivalent for the extra trouble. I usually 

 begin to haul after my crop is "laid by," and it remains in the heaps until 

 about the following February, when it is spread and ploughed in. 1 have 

 spread some and let it lay on the surface twelve months before it was 

 turned under, but I never saw any advantage from it. I have a small piece 



