The moon in the latter part of May was sweeping continuously through our starlit sky in great high circles.

The weather generally was good, with constant minus temperatures.

The log on May 27 recorded: "Brilliantly fine clear weather with bright moonlight throughout.

The moon's rays are wonderfully strong, making midnight seem as light as an ordinary overcast midday in temperate climes.

The great clearness of the atmosphere probably accounts for our having eight hours of twilight with a beautiful soft golden glow to the northward.