Dear Avira,
Rav Hirsch was using a scientific position which is now known to contradict thousands of known phenomena. This not a questionable matter, as Rav Hirsch himself says that we would discard our theories when they are not in conformation with even one known instance. You should follow the truth that Rav Hirsch was not stating that this is an eternal truth. He was understanding the science based on what he knew from the Torah.