Why do clock faces have iiii

This is a very efficient system, but died out almost entirely in the early 18th c.. Like so many others I wondered about the presentation of the number four on roman dials. I think that there might be another explanation for using the IIII form, an explanation I have never read so far. What about the simple explanation that using IIII would build a dial that has four hour-indications using a I; four indications that use a V and four indications that use an X.

November 8, in News. Newsletter Signup. The notation IIII was used for the clock at the earliest Wells Cathedral, which was built at the end of the 14th century in England, and has been conventional since then.

Somebody thought IV was not easily understandable because it resembled VI and was also well balanced with VIII, which was placed in its symmetrical position.

In fact, you can see the notation IIII on mechanical turret clocks that were made before around the 17th century. The most popular theory is that the notation IIII has become conventional in the industry because it looked well balanced on the radial dial plate design and has remained on clocks and watches ever since.

Most modern or vintage watches and clocks rely on a mix of additive notation and subtractive notation where the 4 is IIII and the 9 is IX. With this combination, you obtain three identical areas on the dial, each of them using the same kind of numerals.

The first third only uses I, the second third is the only one using the V and finally, the last third is the only one featuring numerals with X. Also, in the same vein, the numeral IIII is easier to read than the numeral IV, especially when it is upside down, as often on modern watches — where Roman numerals are applied or printed radially pointing to the centre of the dial. Still, not one definitive answer, but a mix of traditions, ancient practices and practical reasons might explain why the watchmaking industry still, today, relies on the use of IIII on most of the dials featuring Roman numerals.

And of course, there will always be exceptions to the rule…. What an informative and fun article to read! Thank you Brice! Thank you Monochrome. My favorite blog by far. It might be a rare Roman striking clock. Very fun read! Most interesting is the cost and ease argument for clock makers using casts and molds for their parts. What this excellent article has missed is that the mold for IX can be turned upside down to give XI and save effort and money but this is not possible for IV.

That is to say using IX for 9 saves money and time but using IV for 4 does not. So the cost of casting argument is actually stronger than presented here. Yes you can use the mould of VI for IV.

Just mirror it not upside down but left to right horizontally. I heard of another explanation. You cannot do the same with IV. This was told to us in school. Actually, the lazy and smart clockmaker option is likely the better of the lot. The way the author describes the moulds would lend credence to his opinion and if the moulds were made as he envsioned, I would agree with him. However, considering the materials availble in the time period most clockmakers made clocks and also those who wanted clocks made like royalty and rich people, I think that they would create as few molds as possible yet small enough to be workable.

Using I I I I instead of IV allows the casting of this mold only 4 times to not only give the least number of pours but also, and likely the most important, least amount of waste.

Would this not apply to other numbers too? Conceited for sure but there were clocks with IIII long before him and I doubt clock makers in countries outside France would adhere to anything he demanded.