41. A black cloth is required to keep stray light out while observing the image on the ground glass focusing screen. 42. Ground glass joint ( or ground glass stoppers ) are commonly used with laboratory glassware, mainly because of their nonreactivity. 43. Ground glass joint ( or ground glass stoppers ) are commonly used with laboratory glassware, mainly because of their nonreactivity.44. Stopcocks are a smooth tampered plug or rotor with a handle, which fits into a corresponding ground glass female joint. 45. The stopcock is a smooth tampered plug or rotor with a handle, which fits into a corresponding ground glass female joint. 46. The apparatus consists of an electric heater with a digital thermostat and two or more bulbs connected with ground glass joints. 47. The ground surface of the barrel moves freely within the ground glass surface of the syringe chamber with very little friction. 48. Sodium hydroxide is also mildly corrosive to glass, which can cause damage to glazing or cause ground glass joints to bind. 49. A petite, elegant woman who favored high heels and silk, Lederer had delicate features and a voice of pure ground glass . 50. In medicine, " Orphan Annie eye " ( empty or " ground glass " ) papillary carcinoma of the thyroid gland.
