一— ö 合 —— 
in spite (H an apparent economy iu employing tlie latter ; for the iron acts more 
efficiently wlien tlio stresses iliereon are not irausmitted to too many parts. 
Angle stifleners for these members are preferable to tees or channels : they 
should bo made flush witli tlie vertical legs of the flange angles by filling plates» 
instead of being bent around the flanges, and at tlie same place there should always 
bo one on each sido of the web. 
In making turn bucklos, a littlo expense can be saved by having only one adjust- 
ing- end ; the other haying a hole, through which passes one end of the rod, which is 
enlarged into a head. One advantage of this style is, that tlio turn buckle can never 
bo lost from tlio rod. Such a turn buckle blioukl always be used on portal vibration 
rods, for a reason that will be given iu Chapter XXII. 
