28

August 26, '49

Fine tin powder was made from CP tin by filing.
Total amount = 7.5 gms in 3 cc. Density = 2.5 gms/cc

A search coil was immersed in this tin powder. No
reduction of radio signal by comparison of the output with
that by without tin powder. No shielding effect was
observable.

Sample Sb #4

Dissolve 21 gms of SbCl₃ into 12 c.c of warm
soln. Stand for a few days. Pour the 7 cc clear soln
into a test tube & add two c.c of conc. HCl.
The precipitate rejected. Contains min SbCl₃
1 gm/c.c. ~ 5 Molar of Sb