THE IMPROVEMENT OF RIVERS. 



necessary for the construction of the masonry and of the approaches, and for proper 

 facility of navigation. 



Measurement for excavation will be made by cross-sections of the bank and river-bed 

 taken just before beginning the work and at such times then-after as maybe necessary. 



23. Disposal. Excavated material shall be deposited as directed and where 

 directed by the Engineer, and in sueh manner as not to interfere with present or pro- 

 posed navigation. Material of any kind deposited by the contractor in absence of, or 

 in disregard of, the instructions of the Engineer, shall, if so required by the Engineer, 

 be removed and re-deposited by the eon tractor at his own expense. If the contractor 

 desire to save any part of the excavated material for later use as embankment, the 

 place of its deposit must be subject to the approval of the Engineer. 



24. Shoring. If deemed necessary for any excavation, it shall be securely shored 

 and curbed by the contractor, with timber and plank, as directed by the Engineer, 

 and shall be maintained by the contractor in this condition until the foundation shall 

 have advanced sufficiently to allow the shoring and curbing to be removed. The 

 piling and lumber thus used will be classified and paid for as " Piling" and as "Coffer- 

 dam Timber" respectively, and shall become the property of the United States. After 

 the necessity shall have ended, the material shall, in the discretion of the Engineer, 

 be allowed to remain in place, or shall be removed and piled by the contractor, in such 

 manner and in such place as may be directed, without extra expense to the United 

 States. If required to do so, the contractor shall use, in any other curbing and shoring, 

 such of this material as may be judged suitable by the Engineer, and for such use, 

 including the labor of erection, with all spikes, bolts, etc., he shall receive 50 per cent 

 of his price bid for similar new material. All nails, spikes, bolts, and other fastenings 

 employed in the shoring and curbing shall be furnished by the contractor without extra 

 cost to the United States, and shall pass into the possession of the United States with 

 the lumber. 



25. Embankment. This will comprise the filling behind the lock-wall and the land- 

 cribs, and any filling required in grading the banks which shall be specifically ordered 

 as "Embankment" by the Engineer. All material used as embankment must be satis- 

 factory to the Engineer. Material, to such an extent and in such locations as the 

 Engineer shall direct, may be taken by the contractor from the banks of the river on 

 the United States land. The cost of excavating the material used will be included in 

 the price of " Embankment," except as it may already have been estimated and paid 

 for as "excavation" and saved by the contractor for subsequent use as embankment, 

 in which case the total payment for it will include the classification as " Excavation," 

 and also as " Embankment." Embankment shall be commenced, carried on, and 

 suspended at such stages of the construction as the Engineer shall direct, but no em- 

 bankment shall be placed against masonry just completed. The grades for embank- 

 ments cannot be given exactly until after all excavation has been made. The con- 

 tractor shall have the privilege of using as embankment such of the excavated material 



