If President Roosevelt had followed the recommendation of the majority of the board of consulting engineers in favor of a sea-level canal, it seems probable that the United States would have followed the French in retiring defeated from the Isthmus, or else would have reconsidered its purpose to build a sea-level canal and have undertaken a lock canal, as the French had done. But, even if it had been possible to build a sea-level canal at Panama, it appears that such a canal would not have been as satisfactory as the present one. While the canal the United States possesses at Panama to-day is a great waterway 300 feet wide at its narrowest part, in which ships can pass at any point, the sea-level canal projected would have been a narrow channel winding in and out among the hills, too narrow for half its length for the largest ships to pass. Currents, caused by the Chagres River, and by the flow of other streams into the canal, would have made navigation somewhat dangerous. The principal ground upon which the majority members of the board of consulting engineers voted in favor of a sea-level canal was that it was less vulnerable. This contention, in the light of what has happened at Panama, seems to carry no great weight. Such a canal would have required a masonry dam 180 feet high across the Chagres at Gamboa, to regulate the flow of that river into the canal. This dam, very narrow and very high, would have been a much fairer mark than the great Gatun Dam for the wielder of high explosives. Furthermore, while earth dams, like that at Gatun, have weathered earthquake shocks of great severity, masonry dams, like that proposed for Gamboa, have been tumbled to the earth by shocks of much less power. The regulating works at Gatun will take care of a volume of water approximately twice as great as the Chagres has ever brought down. On the other hand, the proposed dam at Gamboa would have cared for only one-third as great a discharge as the highest known flow of the Chagres. It was calculated that the lake made by the dam at Gamboa would always be held at low stage between floods, but if two floods came in quick succession this might have been impossible. Such a situation would have made the Chagres River always a menace to the canal, instead of its most essential and beneficent feature.