When I was looking yesterday I came across the term "French Cleaning" (sometimes "Dyer and French Cleaner"). Not something I've heard of before, but apparently a precurser, or type of dry cleaning.
Can't see any particular reference to Lewis Bertolle, though haven't tried multiple spellings. There are these interesting bits about dyers and cleaners in the Paisely area. (Interesting too that in the original article I posted yesterday, the advertiser hired someone who was originally from Edinburgh.)
Walter HOGG, "silk, cotton and woollen dyer and cleaner in Paisley", bankrupt in 1877.
Wednesday, Jan. 3, 1877
Publication: Glasgow Herald
This item about the Scottish Dyers and Cleaners Association (a bit later) from:
Friday, Mar. 21, 1913
Publication: Dundee Courier