[1675] Walla Walla v. Walla Walla Water Co., 172 U.S. 1, 15 (1898).
[1676] Skaneateles Water Works Co. v. Skaneateles, 184 U.S. 354 (1902); Knoxville Water Co. v. Knoxville, 200 U.S. 22 (1906); Madera Water Works v. Madera, 228 U.S. 454 (1913).
[1677] Rogers Park Water Co. v. Fergus, 180 U.S. 624 (1901).
[1678] Home Telephone Co. v. Los Angeles, 211 U.S. 265 (1908); Wyandotte Gas Co. v. Kansas, 231 U.S. 622 (1914).
[1679] See also Puget Sound Traction, Light & P. Co. v. Reynolds, 244 U.S. 574 (1917). "Before we can find impairment of a contract we must find an obligation of the contract which has been impaired. Since the contract here relied upon is one between a political subdivision of a state and private individuals, settled principles of construction require that the obligation alleged to have been impaired be clearly and unequivocally expressed." Justice Black for the Court in Keefe v. Clark, 322 U.S. 393, 396-397 (1944).
[1680] Corporation of Brick Church v. Mayor et al., 5 Cowen (N.Y.) 538, 540 (1826).
[1681] West River Bridge Co. v. Dix, 6 How. 507 (1848). See also Backus v. Lebanon, 11 N.H. 19 (1840); White River Turnpike Co. v. Vermont Cent. R. Co., 21 Vt. 590 (1849); and Bonaparte v. Camden & A.R. Co., 3 Fed. Cas. No. 1,617 (1830); cited in Calvert I, 960-961.
[1682] Pennsylvania Hospital v. Philadelphia, 245 U.S. 20 (1917).
[1683] Illinois Central Railroad v. Illinois, 146 U.S. 387, 453, 455 (1892).