What is the number of Ashmolean with 14s Harrison, and image less than 542?
CREATE TABLE "reconstruction_in_the_british_museum" (
  "image" real,
  "smith" text,
  "ashmolean" real,
  "foster" real,
  "hahland" real,
  "dinsmoor" text,
  "hofkes_brukker" text,
  "harrison" text,
  "cooper" text,
  "bm_corbett" text
);
SELECT COUNT("ashmolean") FROM "reconstruction_in_the_british_museum" WHERE "harrison"='14s' AND "image"<542;