A series of four types of glasses was supplied for investigation. Six individual filaments of each glass (each filament ranged between 7 and 10 μ in diameter) were extracted and the ultimate tensile strength determined for each. The ultimate average tensile strength was then used in the determination of the tensile load applicable to the investigation.
Two methods of examination were used—the Laue and a modified rotation camera. The results of the investigation seem to indicate that a reconstructive transformation in three of the four glasses studied was in process. These results have not been confirmed, due to time limitations. In the case of the E glass investigated, a series of rings were faintly produced after 15 days under 35% of the ultimate average tensile strength. These rings, actually egg-shaped ovals, appeared at 15, 20, and 30 mm from the point of contact of the incident beam. In the other modified E glass and in the YM-31A (BeO) glass, the egg-shaped configuration did not appear in the rotation camera, but did appear in the Laue examination as a semioriented series of spots.