l8o SALT PANS OF THE COAST REGION. 



(2) Certain areas boarded in to keep out mud soon became 

 filled with organic growth of a red or darkish colour, and unless 

 brine be pumped thereon such areas soon became useless. 



(3) The impregnated mud. clay, or sand or the capillary 

 attraction should in theory keep rain water sufficiently supplied 

 with brine to make salt. 



(4) Wells at a depth of 15 to 20 feet give good supplies of 

 brine, and at a distance of six miles from the pan two test dril- 

 lings have, at 40 to 80 feet, shewn strong streams of brine to be 

 flowing underground. Neither these wells nor the underground 

 streams are affected by the ocean tides. 



(5) The strata of salt-pans usually consist of mud, clay, 

 red marl, sandstone and of a black shale. 



(6) In the Free State and northern Cape Colony it is 

 necessary to cut through the black shale or rock before brine is 

 tapped, and without digging wells and pumping brine few pans 

 could produce salt. 



When visiting a salt-pan either near the coast or up-country 

 one is sure to observe in parts of the pan, at certain times of 

 the year, a red colouring. This red colour is erroneously thought 

 by the natives and many others to be due to an excess of salt- 

 petre in the brine. For some time I was inclined to believe this, 

 owing to the blinding sharpness of the brine after heavy working 

 or extreme heat. I have been able closely to observe this reddish 

 appearance, and am now convinced that it is an organic growth, 

 caused in the first instance by an excess of fresh water in certain 

 parts of the pan, and when the brine becomes stronger this red 

 growth becomes more confined and prominent. Stagnant streams 

 or ponds also shew this growth. 



In salt-pans near the coast small shrimp-like creatures that 

 live and thrive in the strongest brine (both surface and well) 

 may be observed. This " shrimp," I believe, feeds on the red 

 growth and assists in preventing it from becoming a menace to 

 the industry. In up-country pans, where I have found that the 

 " shrimp " does not exist, the red organic matter is a pest. 

 ( rystals of Calcite (or Aragonite) are found deposited in the 

 sand and clay of the salt-pans at the coast and also in the salt- 

 pans of the Orange Free State. Black shale is found in the 

 vicinity of the pans at a depth of about 20 feet. This shale Is 

 probably what was found by the Missioners many years ago and 

 was thought to be coal. I have a letter, dated 1834, reporting 

 the discovery. It was most sanguinelv expected that good coal 

 would be found by penetrating deeper into the ground, and that, 

 in view of the coining Steam Navigation, Bethelsdorp would be 

 rich indeed. 



The comparative yield of the pahs inland as against those 

 near the coast is very interesting. For instance, as previously 

 slated, the yield at Zwartkpps does not exceed half a bushel (30 

 lbs.) per square yard of worked area, while the yield of the nans 

 in the Free State is 12 bushels per square yard per season. This 



