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Over the entire area examined it was found that the currents were nearly uniform, and 

 were produced by the tides. In the fresh-water rivers, the Savannah, Ogeechee, Altamaha, and 

 Satilla, the velocity of the current on the ebb was of course augmented, while that on the flood 

 was retarded. Wherever the vessel was anchored, current observations were taken, and for any 

 particular place it was noticeable that the strongest current (greatest velocity) occurred when 

 the flood had run about four hours, or two-thirds high water; and similarly the strongest ebb 

 took place after the water had been falling about two hours. All the current observations 

 were made on the surface of the water. 



It is believed that the currents, ranging, as they do, from i to 2 knots per hour, present the 

 most favorable features for the successful and rapid growth of oysters that can be claimed for 

 the waters examined. 



For the purposes of this report the rise and fall of the tides may be regarded as uniform 

 for the entire area. For the most part, the mean rise and fall is seven feet, and the deviation 

 from this is unimportant. 



In regard to the deposits, it may be said that a certain amount of mud is brought out of 

 the adjacent marshes on every tide, but during the spring tides the greatest amount of deposit 

 takes place, and during this time the entire river in some places was very muddy. 



This almost universal deposit of mud in the waters examined is considered the greatest 

 obstacle to the successful propagation of oysters. It is particularly a disadvantage in the 

 spawning season, when the planter deposits the shells or cultch to get a set. Hence, it would 

 be well to note the time of spring tides in the spawning season, and shell the ground directly 

 after this time. 



The temperature of the water does not change rapidly on the coast of Georgia, and there 

 is no marked difference in the temperature of the northern and southern parts of the State, 

 although there is a difference of about 100 miles in latitude. 



As a rule the oysters are not fat until late in December or early in January, which is prob- 

 ably due to the length of the warm seasons, and, in some localities, to the absence of rains. 



The past winter was known as a very dry season — far more so than the average, and was 

 also a very warm winter. Hence we heard the native oystermen complain that the oysters 

 were unusually poor and unfit for market until January and February. 



Savannah River. — The Savannah River being a well-known and an important commercial 

 stream, scarcely requires for the purposes of this report a hydrographic description. By 

 reason of the large volume of fresh water, oysters are only found in this river near its mouth, 

 where they are kept alive by the influence of the flood tide. The two principal beds examined 

 were those on the Tybee Knoll Spit, and those on the shoal known as the Oyster Bed. The 

 o5*sters are generally poor in quality, and small and well covered with barnacles. Part of them 

 ebb out at low water, while the other part extend into the water for a depth of 20 feet and less. 

 The bottom is more or less shifting, and also shows that deposits are constantly taking place. 

 In a few instances the sounding pole, after probing through a foot or more of surface stratum 

 on the Tybee Knoll Spit, came into a substratum of dead shells. 



On St. Michael's Shoal, and to the northward and westward of it, are found scattering 

 beds of oysters more or less killed by the deposits and the effects of freshets in the rivers. 

 These beds were not surveyed, and are therefore not indicated on the illustration. Samples 

 of the oysters, however, showed them to be superior in size and shape to those on the surveyed 

 beds. But sufficient information was collected to show that it was not advisable to undertake 

 the cultivation of oysters in any part of the Savannah river, unless possibly at or near the 

 mouth of Lazaretto Creek. The improvements to deepen the channel for navigation purposes 

 also render an attempt to cultivate oysters in this river unadvisable. 



Specific gravity. — While making the soundings in this river the vessel was anchored one 

 and a half miles east of Fort Pulaski, in the Tybee Roads, where the average specific gravity ? 

 from twenty-nine observations taken every four hours, was 1.0146. The greatest density was 

 1.0211, and the lowest 1.0084. At low water on the Oyster Bed Shoal it was 1.0090. 



