American Express 189x sans serif printed cancels subtype C, where each of the seven stamps below has the 1 of the 189x year date under the right leg of the X in the AM. EX. CO. portion of the cancel. The following stamp is the "normal" variety of subtype C, with three rectangular equal size periods and normally formed letters.
Reference blog entry from June 14 in which the general scheme used to classify the the different types of American Express printed cancels is shown.
Above stamp: "normal" rouletted variety.