into the walls at where the meridian intersected them, to the points being located with the telescope of the transit. When the frame was set up I got the outer edge of the N-S arm parallel to the line within less than 1/8 inch, measuring with a carpenter's jointed two-foot measure. Balanced the heavy mass in unstable equilibrium, secured it there with the centering set screws, connected the thrust arms with the needle arms and loosened the set screws. Am moderating the temperature of the room by burning a round flame kerosene lamp in it. Thermometer is a Weather Bureau standard minimum (green) placed at 5' above ground on S.W. wall.