TABLE FOR ATMOMETERS 161 



ings have been adjusted, this rod is attached to the axle of the 

 lower hub, thus extending it upward (fig. 1,F). The upper hub 

 is similarly attached by screwing the end of its axle into the upper 

 end of the rod (fig. 2, F). The only necessary modification of 

 the upper hub is the riveting to one of its flanges of a steel plate 

 3 inches in diameter (fig. 2, B), bearing near its outer margin 

 twelve ^-inch openings, equally spaced. Into these openings 

 hook the bent ends of steel bolts (fig. 2, E) which connect, by turn- 

 buckles and second bolts, to guy wires that reach to screw eyes 

 near the outer ends of the wooden arms below. Turn-buckles 

 were difficult to obtain at a reasonable price and common wood- 

 saw rods procurable for a few cents apiece were resorted to. The 

 wire loops at the ends of these were discarded and the heads of 

 the bolts removed. The right screw bolt was bent to hook into 

 the openings just mentioned and the other of the pair was per- 

 forated near its cut end to receive the wire guy. By tightening 

 the turn-buckles, the wooden arms are brought into alignment, 

 the outer ends being raised a little above the level, to put strain 

 on the entire truss system and thus give the table rigidity even 

 without a load. 



The table rests on a standard of iron pipe, screwed firmly to the 

 floor at its center and at the end of each of its four legs. In the 

 upper end of this standard (a six-way casting into which the four 

 legs screw laterally and the centerpiece below, is a plug of Babbitt 

 metal (fig. 1, G), poured around the hexagonal nut which terminates 

 the lower bicycle axle. The hexagonal cavity thus formed is just 

 deep enough to receive the nut, the axle not being allowed to 

 project. 



To fix the upper end of the table axis, a steel plate (1 inch wide 

 and 4 inches long, drilled at its center to fit the axle bolt, fig. 2, H) 

 is slipped over the latter and drawn into place against the cone 

 of the bearing by means of a nut above. This plate is fastened 

 by two wood screws to the end of a wooden thrust arm (fig. 2, I) 

 which extends upward and is fixed to the ceiling of the room. The 

 lower end of this member is cut out at its center leaving a U- 

 shaped opening to allow of the manipulation of the nut above the 



THE PLANT WORLD, VOL, 15, NO. 7, JULY, 1912. 



