Hello,
Your clock is a Model 1166 and listed in Colonial Manufacturing Co. 1914/1915 catalog: case 77 in height, 20 inch wide, 12 inch deep, made of imitation Mahogany quarter sawn oak with French beveled glass.
Since the clock has a German movement; it was probably made 1914-1915 as WWI broke out in 1914 and Colonial would problems obtaining German movements shortly after the war started.
Andy Dervan