MESSRS. W. DE LA RUE AND H. W. MULLER ON THE 
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B REPRESENTS AN ASSUMED MEAN DISTANCE OF THE MOLECULES AT A PRESSURE OF 5 MILLIONTHS OF AN ATMOSPHERE. 
A' TO 10, A' TO 20, . A' TO 40960 THE CORRESPONDING DISTANCES AT PRESSURES 10, 20, 40960 MILLIONTHS. 
