RESULTS OF VARIATION IN FLUIDITY OF METAL. 375
which is seen below at Fig. 71. In using this device to get two test bars, I moulded two separate patterns, in a flask large enough to admit them and having four inches of space between them, so that the gas or heat from the first poured one could not affect the other bar. The flasks were leveled so as to afford like conditions for the running of the metal into the fluidity strips. For chills at the ends of the test bars I used pieces of ^-inch square wrought iron rods, cut to a length of two inches, and loosely set
1 them against the
k-----------10"---------H------JttfJ ends of the pat-
, Knife Edge_____________& thick^ ] \ ^
tern when rnould-
Pauriny {~J Gate
-^c x' H 1* x
V* thick
Fluidity Strip
ing. Should any one desire to cast
Ha I finch square Test liar 13 long I tWO barS at the
..... same time in one
flask, they would
require, of course, but one gate, and it in the middle, leaving the fluidity strips on the outside of each bar. Fluidity-measuring testing tips, cast on test bars, are an entirely new departure originated by the author, and found by him to be of much value when very close records are desired for comparisons of chill records, etc. The plan devised for using fluidity strips with test bars cast on end is described and illustrated in Figs. 121, 122, pages 509 and 514.d one j£ inch, a difference of •£$ inch.