yes but it wrong, on a clock you would use the modified version of the Roman numerals , I, II, III, IV. because you are not counting, the old version of the Roman Numerals was used to count numbers on a stick. IIIIVIIIIXIIIIVIIIIX one mark for every one, a v mark for every five, usually up side down, and a X mark for every ten. So If you went that way 1= I, 2= II, 3= III, 4= IIII, 5= IIIIV, 6= IIIIVI, 7=IIIIVII, 8= IIIIVIII, 9= IIIIVIIII, 10= IIIIVIIIIX, 11= IIIIVIIIIXI, and 12 would be IIIIVIIIIXII. and to be technically correct Roman numerals only have the bars on top and bottom of the numerals when there multiplying.