She could very easily do so unnoticed. From the outside of a house, when it is light, one cannot see what is going on in a dark room.
This question Count Vavel was given an opportunity to decide.
The astronomical calendar had announced a total eclipse of the moon on a certain night in July. The moon would enter the shadow at ten o'clock, and reach full obscuration toward midnight.
Ludwig had persuaded Marie to observe the phenomenon with him; and the young girl was astonished beyond measure when she beheld for the first time the full moon through the telescope.
Ludwig explained to her that the large, brilliant circles were extinct craters; the dark blotches, seas. At that time scientists still accepted the theory of oceans on the moon. What interested Marie most of all, however, was the question, "Were there people on the moon?" Ludwig promised to procure for her the fanciful descriptions of a supposed journey made to the moon by some naturalists in the preceding century. Innocent enough reading for a girl of sixteen!
"I wonder what the people are like who live on the moon?"
And Ludwig's mental reply was: "One of them stands here by your side!"
After a while Marie wearied of the heavenly phenomena, and when the hour came at which she usually went to bed she was overcome by sleep.
In vain Ludwig sought to keep her awake by telling her about the Imbrian Ocean, and relating the wonders of Mount Aristarchus. Marie could not keep from nodding, and several times she caught herself dreaming.
"I shall not wait to see the end of the eclipse," she said to Ludwig. "It is very pretty and interesting, but I am sleepy."