Do you need to write 2011 using Roman numerals? It's easy!
2011 = MMXI
Note the fact that if you use the Roman system the numer 2011 cannot be considered "lucky" as it is sometimes believed when two parts of a given number add up to the same value, which is clearly the case if you stick to the Arabic numerals:
And for all of you sports fans out there, Superbowl numbers in Roman numerals, truly one of the major sources of interest towards the ancient numeric system. Of course, the very first Superbowl did not have a number at first, but the rest of the sure did. I believe every Superbowl also had an official logo.
It is usually assumed that the correct way of expressing number 9 in Roman numerals is IX. This assumption is generally correct, but very often you will see number 9 shown as VIIII. Although this looks quite strange and almost wrong to the modern eye, this was a completely valid way of writing 9 in Roman times. My theory is that using VIIII instead of IX creates a sense of a natural progression of numbers. If you decide to use this old convention for your own numbering purposes, make sure that instead of IV you use IIII for 4, otherwise the resulting numbers may look inconsistent.
I decided to enumerate (pun absolutely intended) all the uses of Roman numerals today. Granted, this will not be a complete list at first. I may never even get to the bottom of the issue, but this should be useful anyway...
Introductions, section numbers, volume numbers etc. in modern books
After the names of monarchs, popes and royally conceited individuals
Dates on buildings
Dates in copyright information (movies, especially)
Sundials are typically associated with Classical Antiquity and for a good reason. They were widely used in Ancient Greece and Rome. The simplicity of their construction made them a lot more affordable than, for instance, clepsidras. As a result, Roman numerals are still traditionally used on sundials. This particular one uses IV for 4, and not IIII as is often seen on mechanical clocks. I actually have encountered a book claiming that Ancient Romans never used IIII instead of IV, but clockmakers have somehow adopted this erroneous representation of number 4. Well, that is simply not true. At this time I am not going to provide any epigrapic evidence, but let me just mention that IV would have also been used as an abreviation for IVPITER, Jupiter. To avoid confusion it was quite reasonable to use IIII. I also believe that on a clock with 12 numbers IIII (And VIIII for 9, incidently) provides a better sense of progression of time (see Ucello's clock), because time is all about forward progress, while the more accepted variations of these numerals imply looking back and subtracting the first part of the compound numeral from the higher value of the second part. Well, you know what I mean. The sundial clock, however, is not capable of showing 12 hour time. It is possible that using classic forms for IIII and IV helps create a more balanced look. Anyway, here is how to make a sundial clock, as described by Archibald Williams in Things Worth Making. Just remember that the present daylight savings time system has to be accounted for. Also, I would suggest picking a sundial motto, as it is quite customary in the business of sundial making.
A HOME-MADE SUNDIAL
A sundial is an interesting thing to have on a garden wall
or the stump of a tree, or to set in a south-facing window. Ordinary flat and
vertical sundials require the use of advanced mathematics; but that to be
described is within the capacity of any handy person.
One begins by making a cross of thin metal. Brass, copper,
zinc are all suitable; copper is the best. The cross may either be cut in one
piece out of the sheet, or be compounded of a vertical piece and a cross piece
riveted together at the point of crossing. The dimensions given in Fig. 44, a,
are for a small dial, but they may be modified to suit individual fancy,
provided that the circumferential length of the cross-piece B be the same as
the distance between the centres of the holes in A. Mark off the cross-piece
into twelve equal parts, and subdivide each of these into quarters or twelfths.
The lines may be scratched or etched with acid. For the hours use the Roman
numerals, which, being made up of straight lines, are very easily engraved.
When this has been done, bend both pieces to a truly
semicircular shape. To get the curve correct one must cut out a cardboard
circle with half its circumference equal to the length of the crosspiece piece
and use it as a template. The exact diameter can best be arrived at
experimentally. If copper or brass be used, anneal it by red-heating and plunging
into cold water before it is bent.
As the pieces are easily distorted, if of thin metal, it is
advisable to solder to the back of each a rib of the same metal, cut out with
the aid of the template already made. One rib will have to be severed at the
crossing-point to give room to the other rib, to which it should be soldered.
If stout strip metal be used, this backing will be unnecessary, but in this
case a wooden template had better be cut to the right curve to enable the
shaping to be done accurately by hammering. After shaping, slip a piece of
quite straight copper wire through the holes in A, and make them fast with
The dial is now fixed facing the south (in our northern
latitudes), with the wire sloping towards the north, and making with the
horizontal an angle approximately equal to the latitude of the place --for London,
about 51 1/2 degrees. To state the matter otherwise, the axis of the wire should
point to the Pole Star. The orientation must be established accurately by a
The dial is most easily fixed by means of a little wooden
saddle crossing A, with a screw at each end penetrating either a horizontal
base board (as shown) or the face of a wall -- in which case the saddle would
occupy the position indicated by the dotted lines.
When consulting the dial at any time, add or subtract the difference for the day from the shadow
reading to arrive at clock time. At most the
difference is only about a quarter of an hour.
Robert Yerkes of Harvard reported the following experiment in Science XX, No 505 I have chosen ten well-educated, and in most cases scientifically trained individuals, and determined for each the time necessary for the writing of the Roman and the Arabic numerals from 1 to 100 and the number of errors made, also the time necessary for the reading of the Roman and the Arabic numerals from 1 to 100 when they were irregularly arranged so that the reader did not know what order to expect. In all cases the number of errors made unconsciously was recorded. These measurements furnish the following startling averages: It takes three and one third times as long to write the Roman numerals from 1 to 100 as the Arabic, and the chance of error is twenty-one times as great; it takes three times as long to read the Roman numerals from 1 to 11O as the Arabic, and the chance of error is eight times as great.
In case of a quick and accurate mathematician, whose familiarity with the Roman system surpassed that of most of the individuals tested, the results were: time for writing Arabics, 107, errors, 0; time for writing Romans, 357, errors, 5; time for reading Arabics, 62, errors, 2; time for reading Romans, 131, errors, 5. For one well-trained scientist, who has cause to use the Roman system almost every day, the number of errors in the rapid reading of the Romans was 151 These figures certainly indicate the desirability of using the Arabic system wherever there is no urgent need for the simultaneous use of two or more systems of numerals. Even if there were no saving of time and strain by the avoidance of the cumbersome Roman symbols, the far greater accuracy gained by the use of the Arabic system should at once settle the matter for all scientists.
Interesting results. I would like to note two things, however. The Roman system is slightly more aesthetically pleasing and even more appropriate in certain cases. In books, it allows to have separate pagination for the introductory part etc. Also, from the point of view of the information theory, the system that intrinsically involves using more symbols should be more redundant and less prone to transmission errors. I think that, above all, this experiment proves the need to learn Roman numerals and to develop better control over them.
One of the most curious uses for Roman numerals consists in rearranging the letters within a numeral in order to produce a recognizable word in Latin or some other language. I don't think that many actual numerals can be read as words without such rearrangement, but with some creativity interesting cases can be found. Such is VIXI, generated from XVII (17)
Claude GagniÃ¨re says in Au bonheur des mots:
The Italians fear the 17's, because 17 is written XVII in Roman numerals, which is the anagram of VIXI, which means "I lived", i.e. "I am dead". In Italy, buildings do not have a 17th floor, hotels do not have a room 17, and Alitalia planes do not have a seat 17 [neither do Air Inter planes and British Airways Concordes]. When Renault marketed its R17 and wanted to export it to Italy, it had to be renamed "Renault 177". Napoleon Bonaparte, who was more Italian than French in his education, refused to give the signal for his coup on "vendredi 17 brumaire" and postponed it until the following day.