Roman numerals, a numeral system of Ancient Rome, based on letters of the Latin alphabet, remains one of the most popular decimal systems in use today.
One look at any mathematical formula in Roman numerals is enough to realize that to use this system for anything complex would be extremely difficult, if not impossible. It takes forever to simply right down most numbers! The truth is, the Romans were not overly patriotic when it came to number systems. All the feats of engineering, temples, arenas and palaces would have never become a reality were it not for the ample use of Greek numerals! Roman engineers and scientists were usually either Greeks or Greek-educated Romans (sometimes completely bilingual). The Greek system was much more versatile, compact and well suited for any calculations known to Ancient mathematicians.
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.
When modern students are faced with having to learn the Roman system they often wonder how on earth anyone ever found this number notation convenient for any sort of calculations. The answer is actually rather simple. Yes, Roman numerals are not great for complicated calculations. However, they were extremely convenient when they were used at the time of their origin. Imagine having to carve Arabic numerals on wood or bark. Now imagine achieving the same objective using Roman numerals. The difference is striking. All the letters used in the Roman system can be carved with a few simple cuts: I, V, X, L, < (for C), |> (for D), M. There is evidence that a similar system was still used in the 19th century, in some rural communities in Italy, by shepherds who needed to keep track of their flocks. By the way, the simplicity of these symbols may indicate that they are not related to the Latin alphabet, but are rather independent of it, except perhaps C and M, which are probably dependent on the Latin words centum (one hundred) and mille (one thousand).
Come Superbowl time, every football fan in the US is subject to a mandatory annual rediscovery of Roman numerals. Of course, the proper way of referring to Superbowl match-ups requires the use of this antiquated, yet beautiful system. Apparently, this yearly refresh course is not enough for some people. This t-shirt that was made by the University of Florida in 2006 should serve as a somber reminder of the sad state of affairs in our education when it comes to Roman numerals. Instead of MMVI (2006) these shirts were printed as shown, proudly displaying XXVI (26). To all math teachers out there, use this in class to prove to your students that not knowing how to use Roman numerals can can you fired!
The ultimate Roman numerals chart! This guide is an essential reference for everybody who has to deal with
Roman numerals. Includes a Roman numerals chart (1-5000) and a look-up
table of alphabetically arranged Roman numerals, with some variants and
erroneous renditions.
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.
This passage is taken from Number Stories of Long Ago, by David Eugene Smith:
Titus liked to puzzle a chum of his named Caius, and one day he asked him this question : " What is the number that becomes one more when one is taken away from it ?"
"Your head," replied Caius, "must be just plain wood."
But when Titus wrote IX on the stone pavement and said to Caius, "Now take away the I and tell me what you have left,"Caius saw that the wooden head had something in it after all.
Then Caius, remarking that he could think of many other numbers that would answer just as well, asked this question: "What is the number that becomes ten more when ten is taken away ? "Titus then asked Caius if he knew that half of nine was four, and Caius replied that he must be dreaming. But Titus pointed again to IX and asked Caius to take the upper half of it and see if it was not IV. Then Caius said that he could show that half of twelve was seven.
"That is nothing," said Titus; "half of thirteen is eight."
"That is easy," said Caius ; "but can you take one hundred from four hundred and have five hundred left ?"
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...
Clocks
Sundials
Introductions, section numbers, volume numbers etc. in modern books
After the names of monarchs, popes and royally conceited individuals
Centuries
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
solder.
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
compass.
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 noon difference for the day from the shadow
reading to arrive at clock time. At most the noon
difference is only about a quarter of an hour.
