Sentence:  In the teache the subject is still further evaporated, till it is judged sufficiently boiled to be removed from the fire. This operation is usually called <WSD>striking</WSD><!--bold instead of italics-->; (i.e.) lading the liquor, now exceedingly thick, into the cooler. 
Meaning of the word marked with <WSD> tags:  To lade thickened sugar cane juice from a teache into a cooler.