What is the Gauge of Builder Beyer, Peacock?
CREATE TABLE "0_6_0_0_6_0_garratt_production_list_all_" (
  "gauge" text,
  "railway" text,
  "works_no" text,
  "year" text,
  "builder" text
);
SELECT "gauge" FROM "0_6_0_0_6_0_garratt_production_list_all_" WHERE "builder"='beyer, peacock';