I think, he used a to-do list in order to proceed meaning it was not an ultimate aims, but rather he could use measurements, information from the people for further work. Modern to-do list is more like "done (will never come back to it anymore)".

Also, he was not an unsociable genius. He was curious not only about accumulating knowledge, but rather to find out how things are made which is quite practical. Undoubtedly, it was such a marvelous time in the history, when people discover the world in the whole directions.

Thank you for writing!