of the lock. The blockheadedness of the Spaniard is most clearly shown in the attitude of a certain state paper, though, in fact, it very nearly voices a fundamental scientific law; with reference to the canalization of Spanish rivers a decree of a state council read: " . . if it had pleased God that these rivers should have been navigable, he would not have wanted human assistance to have made them such, but that, as he has not done it, it is plain that he did not think it proper that it should be done. To attempt it, therefore, would be to violate the decrees of his providence, and to mend these imperfections which he designedly left in his works." There was a vast deal of mending the imperfections of Providence before men found the secret of one of Providence's simplest laws.
In 1481 two engineers at Viterbo, Italy, invented the canal lock by which craft could be lifted or lowered from one level to another. The discovery gave great impetus to canal building, especially in Italy. The first canal in France was the Braire, built in 1605–1642. The Orleans was opened in 1675. Of all European works of
