The Montgomery advertiser., 1904-12-19
Engineer Wallace On the
 Canal.
TWENTY YEARS OF WORK
Ditch to Cost Nearly Three
 Hundred Million.
Many Laborers, Maehinists and En- gineers, are New Busily Begin- ning Work of Connecting
 the Two Great Oceans.

Washington. Dec. 1s.--Mr. John F.
 Wallace, chief engineer of the Isthmian
 Canal Commission. has given to the
 House Committee on Interstate and
 Foreign Commerce the beneft of his
 investigations so far as made regarding l the engineering tasks to be performed
 in the construction of the Panama Ca- | nal.
 l The testimony was taken aboard the
 army transport Sumner in Colon Har- | 'bor. on the occasion of the recent
 visit of the committee to the Canal
 Zone. It Is to be printed for the use l of Congress.
 l The Associated Press has the benefit I of the testimony in advance of its pub lication. through the courtesy of Chair l man Hepburn and Secretary Cushman of the commission. Before taking up | in detail the four distinct canal propo- sitions which are being considered by him, and on which he Is to report to 1 the Canal Commission, Mir. Wallace made this explanation of the general l problem: The isthmus Is traversed by a noun tain range the summit of which Is ap- proximately twelve miles from the Pa- cific and thirty-five miles from the Caribbean. Originally a gorge evi dently existed from the Caribbean near Colon to the vicinity of Gamboa and extended beyond that point in an east erly direction, forming the upper basin of the Chagres River. After filling this gorge with an alluvial deposit, the Chagres has swung itself from one side of the valley to the other. The result &u xh~% nf ho tvfn nal cannot be followed or found from sur face indications, and 1t Is only by drill ing to bed rock that exact information in regard, to any particular locality can be obtained. ,,,
 The presence of boulders in this aIlu- vial deposit also explains the reason when engineers. not taking time to go into the rock far enough to determine It's actual character. have been misled into thinking they had struck bed rock. To determine the most feasible plan for the construction of the canal will re- quire a months careful and comprehen- sive examination, not only of surface conditions, but the sub-surface must be explored.
 After following the valley of the Chargres to Gamboa. the line of the canal follows a tributary, called the Obispo. up to the summit of Culebra, and thence follows down the valley of the Rio Grande into the Bay of Pan- anna. The summit at Culebra was originally about 300 feet above the sea level. and is the lowest point in the divide along the entire length of the isthmus of Panama. The plan of the former commission provided for dam of practically 100 feet in height above the sea level, at Bohio. with water level of 90 feet above the sea level
 This place was selected on account of the fact that at that point the hills on either side of the Chagres come comparatively close together, being about 1,50O feet apart, and from the surface indications 1t seemed favora- ble place for the construction or a dam. Rut the indications are that this Iocality will be an unfavorable and ex- nensive one for the construction of a high dam.
 .Srbe instructions to the chief en- xineer by the present commission are that he Is to make full and thorough examinations of the canal route, the manner of doing the work and the various plans which might suggest themselves and lay before the commits sion the result of this examination with his final recommendations
 
 ana estimated upon by the former com mission, is the possibility and prac- ticabiIity of a high dam or proper foundation for a high dam at Bohio. upon which depends the advisability of constructing a high level canal with the surface of the water ninety feet above sea lever.
 .0The second plan under considera- tion is a summit level of sixty feet above sea level. Constituting canal on this plan admits of two different methods of treatment: FTst' the con struction of a dam sixty feet above sea IeveI at Bohio, with two locks of thir- tv feet there being two locks on the western slope; second, the construc- tion of a dam sixty feet above sea level at Gatun, eight miles from Colon with two thirty foot locks in the same vicinity.
 The adoption of sixty foot level also will render 1t necessary to con- struct a dam at Gamboa in order to provide a reservoir to accumulate water enough during the wet season to fur nish water for the summit level of the canal. The construction of a dam at Gamboa in this connection would also control the Chagres River. except that it would be necessary to provide safety spillway by the construction of a tunnel some eight miles in length through the divide. discharging the surplus waters of the Chagres into the headwaters of Juan Diaz or the alter native plan of constructing a tunnel four miles long through the divide separating the Chagres basin from the headwaters of the qatuncillo, a stream which enters into the Chagres valley at Gatun. Should this latter course be adopted 1t would be necessary to con- struct an auxiliary channel for the ChaTres from Gatun to the sea in order to divert It's fioodwaters into the bay eastward of Colon.
 'sThe third general plan under con- sideration would be the construction of A canal with a twenty foot or thirty foot level above the sea with single lock at Mirahores, and a single lock at Bohio or the immediate vicinity; the construction of the reservoir dam at Gamboa to be required In this Instance the same as In the sixty foot level plan
 ''The fourth plan would be the con- struction of a sea level canal with a tidal lock at Mirahores. In this con Hnection 1t is necessary to explain that while the mean sea level of the Pa- cfa, and the Caribbean are fha maxrn