Popular Science Monthly, Volume 71

Academy actinium Agassiz animals appear astronomical become Bell body cable called canals cent character cities cochineal colony cone crater curve cytomorphosis death differentiation early electric embryo established eugenics existence eyes fact feet fiber francs Gardiner Greene Hubbard girl growth human Iceland illustration important increase institutions interest larvæ lava lecture less light lines Linnæus living Louis Agassiz MARIA MITCHELL means ment mental method miles mind mountain muscle museum natural history natural selection nerve cells nucleus observations observatory organization ovum parasitism parent period physical plants Polyergus pragmatism present probably Professor protoplasm rabbit radiation radium rays result river scientific seems senescence sexual selection Society species spinal cord stage teachers telephone theory things thorium tion University uranium volcano walls wires young