ear is thick enough an inert nu- bodies, "such as phosphorus, sul- cleus is reached, which breaks under a shock like ordinary phur, certain alloys, etc., experience on being tempered glass. interesting modifications, some of which have been utilized The tear made in the manner above described may… … action to regain equilibrium, and in so doing to destroy the whole tear. If, on the contrary, The tempering of glass and the curious properties thus Fie. 9. the exterior layers are slowly dissolved, the acquired by that substance was first studied during the sev- neck being preserved, the layers…
