Complex sentence: He tracked and regathered Furnivall's collection of quotation slips, which were found to concentrate on rare, interesting words rather than common usages: for instance, there were ten times as many quotations for "abusion" as for "abuse".
Split into simpler sentences: He tracked and regathered Furnivall's collection of quotation slips, which were found to concentrate on rare, interesting words rather than common usages. For instance, there were ten times as many quotations for "abusion" as for "abuse".