Convert from cubit [Royal Egyptian] to ell [English]

Unit Definition (cubit [Royal Egyptian])
The Cubit is a historic unit of distance frequently mentioned in the Bible. The word comes from the Latin cubitum, "elbow," because the unit represents the length of a man's forearm from his elbow to the tip of his outstretched middle finger. This distance tends to be about 18 inches or roughly 45 centimeters. In ancient times, the cubit was usually defined to equal 24 digits or 6 palms. The Egyptian royal or "long" cubit, however, was equal to 28 digits or 7 palms. In the English system, the digit is conventionally identified as 3/4 inch; this makes the ordinary cubit exactly 18 inches (45.72 centimeters). The Roman cubit was shorter, about 44.4 centimeters (17.5 inches). The ordinary Egyptian cubit was just under 45 centimeters, and most authorities estimate the royal cubit at about 52.35 centimeters (20.61 inches).

Unit Definition (ell [English])
The El (or Ell) is a traditional unit of length used primarily for measuring cloth. In the English system, one ell equals 20 nails, 45 inches, or 1.25 yards (exactly 1.143 meters). The word comes from the Latin ulna, which originally meant the elbow and is now the name of the bone on the outside of the forearm. The history of the unit is not clear. Some authorities believe the ell was originally a double forearm length, that is, 2 cubits or 36 inches, the same length as a yard. The ell and the yard do seem to be identified in some medieval documents, with ulna being used for both, and in Scotland the ell was equal to 37 Scots inches or 37.2 English inches (94.5 centimeters), only slightly longer than the yard. (This Scottish length might also reflect an old practice of cloth merchants in giving an extra inch with each yard, to allow for any irregular cutting at the ends of the piece.) However, the English cloth ell is definitely longer than the yard; it seems to be the distance from the shoulder to the fingers of the opposite hand. This reflects a practice of cloth merchants of holding the cloth at the shoulder with one hand and pulling the piece through with the opposite hand. This cloth ell was used with a similar length in France, where it was called the aune. The Dutch el and German elle are a little more than half the English ell; they may represent "arm's-length" units like the Italian braccio, the Russian sadzhen, and the Turkish pik