Origin of Springs. 327 



States comprife a million of fquare miles. Thirty five 

 cubic feet of rain water weigh a ton. A mafs of water, 

 covering 1 ,000,OtX) fquare miles to the depth of 4 feet 

 2 inches, contains 1 1 G, 1 60,000,000^000 cubic feet; 

 amounting to 3,3 1 8,860,uOO,000 tons. 



By an examination of the Map of the United States 

 it will appear, that, on its borders and wdthin it, there 

 are 26 great primary rivers, or rivers communicating 

 directly with the Ocean. Thefe are the St. Lawrence, 

 Penobfcot, Kennebec, Ameriscoggin, Saco, Merrimac, 

 Connecticut, Hudibn, Delaware, and Sufquehannah, in 

 the North ; and the Potowmac, Rappahanoc, York, 

 James, Roanoke, Pamlico, Neufe, Cape Fear, Pedee, 

 Santee, Savannah, Ogeechee, Altamaha, Apalachicola, 

 Mobille, and Miliiilippi in the South. The St. Law- 

 rence receives half of its water from the Canadas ; and 

 more than three fourths of the fupplies of the Miffiflip- 

 pi are furnifhed by Louiliana. Of this the proof is di- 

 rect. The Ohio, the only very large tributary from the 

 eaft, is fmaller than the Arkansas ; and the Illinois, the 

 only remaining eaftern branch worthy of notice, is 

 much lefs than the St. Francis. On the Weft, however 

 there are alfo the Mifoiiri, which is larger than the Mif- 

 fiflippi itfelf before the juncfion, added to all the bran- 

 ches from the eaft j and Red River, which is much lar- 

 ger than the Ohio. 



Of the remaining /(r/w^zry rivers, the Amerifcoggin, 

 Saco, Merrimac, Rappahannoc, York, Pamlico, Neufe, 

 and Cape Fear, are about as large as the Thames ; and 

 the Penobfcot, Kennebec, Ogeechee, and Altamaha, are 

 not much larger. Taking thefe fafts into confideration, 

 I am fatisfied, that, if we admit each of the 26 primary 

 rivers to yield ten times as much water as the Thames, 

 we fliall allow a fufficient overplus to fupply ail the pri- 

 mary ftreamlets. On this suppofition the annual dif- 

 charge of water from all the rivers of the Union will 

 amount to 1,281,660,000,000 tons -.leaving a reliduum 

 of 2,037,200,000,000 tons to fupply the demands of 

 ^evaporation from the land. 



