Doctor in de Wis en Natuurkunde,

This is a collection of scientific articles and papers by Dutch physicist and astronomer Johannes Govertus de Man. The work covers a wide range of topics, including optics, electricity, and celestial mechanics. It is a testament to the breadth and depth of de Man's scientific knowledge and his passion for the study of nature and the universe.

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it.

This work is in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.

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