The Birmingham age-herald., 1904-12-19
Thousands of LaborIng Men Are Already at Work
 on the Isthnus
CANNOT YET MAKE REPORT
 ON TIE ULTIMATE COST
Greatest Difficulty of the Project VIII be Cutting Through the lm- n1ense Culehra-Doubts Ad-
 visibility of Civil Service.

Washington December 1s.-Mr John F. Wallace, chief engineer of the isthmian canal commission, has given to the house eommitte on interstate and foreign com merce, the benefit of his investigations so far as made regarding the engineering tasks to be performed in the construction of the Panama canal The testimony was taken aboard the army transport Sumner in Colon harbor on the occasion of the recent visit of the committee to the canal zone. It Is to be printed for the use of congress.
 The Associated Press has the benefit of the testimony in advance of it's publi- cation through the courtesy of Chairman Hepburn, and Secretary Cushman of the committee.
 Before taking up in detail the four distinct canal propositions which are be- ing considered by him, and on which he is to report to the canal commission, MT. Wallace made this explanation of the general problem:
 The isthmus is traversed by a noun tain range, the summit of which is ap- proximately 12 miles from the Pacific. and 35 miles from the Caribbean. Orig inally a gorge evidently existed from the Caribbean near Colon to the vicinity of Gamboa, and extended beyond that point in an easterly direction, forming the upper basin of the Chagres river. After filling this gorge with an alluyial deposit, the Chagres has swung itself from one side of the valley to the other. The result is that the thread of the orig inal gorge cannot be followed or found from surface indications, and 1t is only by drilling to bedrock that exact surface indications, and particular locanty can be obtained. The presence of boulders in this alluvial deposit also explains the reason when engineers, not taking time to go into the rock far enough to de- termine it's actual character, have been mislead into thinking they had struck bedrock. To determine the most fea- sible ilan for the construction of the canal. will require a months careful and comprehensive examination, not only of surface conditions, but the sub-surface must be explored.
 Provides for Big Dam.
 After following the valley of the Chagres to Gamboa, the line of the canal follows a tributary, called the Obispo, ur to the summit of Culebra, and thence follows down the valley of the Rio Grande into the bay of Panama. The summit at Culebra was originally about 3OG 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 a dam of practically 100 feet in height above the sea level, at Boho. with a water level of 90 feet above the sea level. This place was selected on account oe the fact that at this point the hills on either side of lhe Chagres compara- lively come close together, being about 150O feet apart, and from the surface in- dications it seemed a favorable place for the construction of the dam. But the indications are that this locality will be an unfavorabe and expensive one for the construction of a high dam.
 ''The instructions to the chief engineer by the present commission are that he is to make full and thorough examina- tions of the canal route the manner of doing the work, and the various plans which might suggest themselves, and lay before the commission the result of this examination with his final recommends ticn.
 Depends on Bohlo Dam.
 "The first plan to be considered, the one estimated upon by tine former com mission, is the possibility and practica- bilitv of a high dam, or proper founda- ion for a. high dam at Bohio, upon which depends the auvisability of con structIne a high level canal with the surface of the water 90 feet above sea level
 "The second plan under consideration is A summit level of 60 feet above sea level. Constructing a canal on this plan admits of two different methods Of treat ment: first. the construction of dam 0 feet above sea level at Bohio with two locks of 30 feet, there being two locks on the western slope; second, the construc- ton of a dam 60 feet above sea level at Gatun, eight miles from Colon, with two 30-foot locks in the same vicinity The adoption of a 60-foot level also will render 1t necessary to construct a dam at Gam boa in order to provide reservoir to &C., cumulate water enough during the wet season to furnish water for the summit level of the canal. The construction of a dam at Gamboa in this connection would also control the Charges river, except that 1t would be necessary to provide a safety spiIl-way by the construction of a tunnel some eight miles In length through the divide, discharging the sur plus waters of the Chagres into the head waters of the Juan Diaz or the plan of constructing a tunnel four miles along the divide separating the Charges in Bay from the headwaters of the Gatuncilo, a stream which enters into the Chagres valley at Gatun. Should this latter course be adopted it would be necessary to construct an auxiliary channel for the Chagres from Gatun to the sea. in order to divert it's noodwaters into the bay eastward of Colon.
 Built With Single Lock.
 "The third general plan under consid- eration would be the construction of a canal with a 20-foot or 3O-foot level above the sea with single lock at Mirax Flores, 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 60-foot level plan.
 "The fourth plan would be the construc- ton of a sea-level canal, with a tidal lock at Mira Flores. In this connection 1t Is necessary to explain that while the mean sea level of the Pacific and the ooo oo,,I1 mt ouyfr0' fo f1a darIruaaa nH