4. CONTROL AND SIGNAL BUILDING 



121 



an accident or wear goggles while mixing 

 the whitewash. 



4—31 Entrance on private property. — 



Where stations and signals are to be estab- 

 lished on private property in populated areas, 

 permission must be obtained from the owner, 

 and no damage or defacement of property 

 shall be made without his consent. 



Where surveys are made along the shores 

 of publicly-owned areas, such as parks, na- 

 tional or state forests, or reservations, the 

 superintendent or other official should be con- 

 tacted. This is particularly important if any 

 clearing is required. 



Nothing arouses the ire of a property 

 owner so much as unauthorized entrance on 

 his property. When the nature of the work 

 is explained, there will seldom be any diffi- 

 culty in obtaining permission to establish a 

 station. If it is necessary to damage crops, 

 shrubs, or trees, the regulations must be 

 closely followed in securing beforehand a 

 written agreement which shall state the 

 amount of damages to be paid. When the 

 survey has been completed, signals shall be 

 removed from private property or the owner 

 shall be notified that the signals are no 

 longer needed. 



4-32 Buoy signals. — Before electronic 

 equipment was adapted to control of hydro- 



graphic surveys, various types of buoys were 

 used extensively for control of offshore hy- 

 drography. Detailed instructions for con- 

 struction of these buoys can be obtained 

 from the Washington Office. Floating sig- 

 nals of this type may occasionally be re- 

 quired to control surveys or investigations 

 of small extent. The single-barrel buoy, or 

 a smaller counterpart of it, described in 4-33 

 will be adequate for this purpose. 



The essential parts of a survey buoy are 

 a water-tight drum or barrel for buoyancy 

 to support a target which is held in an up- 

 right position by a counterweight, and suit- 

 able ground tackle for anchoring. A 5-gallon 

 gasoline or oil can painted yellow or white 

 and anchored by a light line attached to a 

 grapnel, makes an excellent marker buoy for 

 a launch hydrographic party. If added visi- 

 bility is required, a light bamboo pole may 

 be secured to the can with a flag at one end 

 and a small counterweight at the other. 



4-33 One-barrel buoy. — The one-barrel 

 buoy, illustrated in Figure 48, consists of a 

 55-gallon oil or gasoline barrel secured in a 

 frame of 2- by 4-inch lumber, cross-braced 

 with 1- by 4-inch lumber. Two cross braces 

 are grooved to fit over the chimes of the 

 barrel at top and bottom, and the barrel is 

 securely held in the frame by half-inch bolts 



List of Materials for One-Barrel Buoy 



Description 



Lumber 



Do 



Do 



Barrel, G.I 



Car coupler (scrap) 



Eyebolt with shoulder and nut, G.I. 



Bolts 



Rods, tie, threaded on both ends . 



Nuts, hexagonal 



Washers 



Washers . .- 



Washer plates, iron 



Counterweight plate, iron . . . 



Shackle, G.I 



Screen, wire, black 



Cloth, muslin, various colors . . 



Rope, Manila 



Nails 



Tacks 



Standard enameled buoy plate or 

 muslin signal notice. 



Size 



2" by 4" by 16' . . . . 



2" by 4" by 10' . . . . 

 1" by 4" by 16' . . . . 



55 gallon 



180 to 200 pounds . . . 



%"by5" 



%" by 7" 



%" by 32" 



%" 



ly*" by ■Vu:" V'/u;" hole) 

 21/4" by y,,i" CyKi" hole) 

 3" by 10" by %" drilled . , 

 3" by 15" by %" drilled . . 



%" 



Medium mesh, 1 yard wide , 



1 yard wide 



3" 



12 d. and 20 d 



Carpet , 



Amonnt 

 Required 



pieces, 

 each. 



4 pieces. 

 1 each. 

 1 each. 

 1 each. 



each. 



each. 



each. 



each. 



each. 



each. 

 1 each. 

 1 each. 



yards. 



yards. 



15 feet. 



1 each. 



