OF SOUTH CAROLINA. 241 
Fromid: Weinglotany sae ...<1 -. 20528 eee ee § ane 62 
ce, = Jeep bunmons's, No; 1... ...scteteee ames aoe aa 544 
“ dow. INO: 25 35 ee eee ee 50 
ee do Nos3 222822: RE ee ee) 48 
The marls of the Peedee are easily recognised, by their dark color: the softer varieties, when dry, 
change toa gray, or ash color. The marl stone has been burned to supply lime, for building—a 
purpose which it is said to answer very well. The upper portions of some of the beds contain 
iron pyrites, which, by spontaneous decomposition, forms sulphuric acid, which, trickling down the 
surface of the marl, in the form of sulphate of iron, combines with the lime and alumina, forming 
sulphate of lime and of alumina. It is found presenting the appearance of effervescence, where it 
is exposed to the atmosphere. I have not, however, seen pyrites in sufficient quantity to be at all 
injurious, and I only mention this fact to show the effects of lime, in correcting what would other- 
wise be injurious. When sulphate of iron is found in the soil, in large and injurious quantities, it 
may be decomposed and converted, as in this case, into sulphate of lime or gypsum. : 
Table of the amount of carbonate of lime in the Cretaceous Marls. Mr. 
Ruffin. 
per cent. 
Throughout this, the soft marl, which is generally rather poor, and the 
very hard and compact marlstone, which is generally rich, are presented 
in alternate layers, 
Marl, dark bluish gray, from bluff at Birch’s F Ferry, carb. lime. -~.36 
do. at Birch’s Ferry, 5 feet from bottom of the bed_33 
do. do. NO Meehe oe. os Soe ere 5L 
Marlstone, do. Ueiieet ste ae a _ 2 66 
Marl, clay wall, (J. A. Jolly’s,) above mouth of Jeffrey’s creek, surface 24 
do. Willow Creek, Gordon’s...-....-_-.--..-2----.0=.----- 45 
Marlstone, Gi, gee nee ees ease eel 
Marl, Bingham’s, on stage road, supposed average of his digging. ..32 
do. Leggett’ S, upper part host oi ee ee ee Eee 57 
do... Giles’s' bluft Henry, Wavisise- sso noe ae ee ee 42 
do do. next to low water mark- -___-.-.14 
Marlstone, do. BO Se EE ee ele 86 
do. Miyersis lands te neecige o> See as ee Saeko 84 
do. do. (another. spectmen)-_— -. = -3 =<.  eee 76 
do. (pale yellow) Gibson’s bluff, upper layer--------------- 82 
Marl, bluish gray, do. lower Ss2o ste zteda ese, 10 
Black River marlstone ledge, at Avant’s (or Brown’s) upper ferry - - -72 
; do. soft black earth underlying the last, only 
Stony Run, Georgetown, marlstone 55 
Marts of Lynch's Creek. 
per cent 
From SPATOW SWAN pst WOPs 2 — a= Sosa he ee LCs 182 
Ba O rot LOC UIC GU [te me ete ete rer ee as kc 21 
<)  TdoweG feet despite S528 See Se eee oe 254 
G) edb. “marlstone.— =.= aa ee eA dee 8 66 
« Henry Ham’s, Sparrow Swamp, 5 feet deep-._--.---------_-- 25 
«  B. Wawrence’s, liynch’s Creek, top-__-.-- .--_--.---_-..__- 15 
« — Furney Ham's do. 6'feet deeplisiss_ Lier es 22: Q72 
“  §. Coward’s do. Sifeet deepsa2 sao ee soe 3. 274 
58 
