A reader, noticing the way the word museum is engraved on some statues and entrances, writes:
I am wondering why the word Museum is spelled Mvsevm . . . on many older things like statues.
Until the twentieth century, classical Latin was an indispensable part of the school curriculum. Anyone who had been to school beyond the age of seven had at least a smattering.
What are now called “elementary schools” or “grade schools” were once known as “grammar schools.” When the term “grammar school” originated, the grammar meant was Latin grammar.
Because Latin was regarded as being much classier than English, it was often used to commemorate special occasions. For example, Latin was the language of choice on diplomas, ceremonial proclamations and stone inscriptions on statues, tombs, and museum entrances.
The classical Latin alphabet did not contain the letters J, W or U:
A B C D E F G H I K L M N O P Q R S T V X Y Z
It did not have what we call “lowercase” letters either. Latin inscriptions, therefore, were written in all capital letters.
The letter V stood for both the vowel sound we represent with the letter U and the consonant sound we represent with the letter W.
During the second century CE the rounded U form of the V appeared in Latin writing.
A carved inscription that substitutes a V where English would use a U is supposed to look like classical Latin. Hence the capitals and the Vs for Us.
Besides, I’d guess that it’s much easier to make a V with a chisel than a U.