id	keyword
hindsight-3601	article
hindsight-3601	optometry
hindsight-3601	issue
hindsight-3601	history
hindsight-3601	board
hindsight-3601	pages
hindsight-3601	book
hindsight-3601	ohs
hindsight-3601	helmholtz
hindsight-3601	new
hindsight-3601	lenses
hindsight-3601	american
hindsight-3601	spectacles
hindsight-3601	optics