In constructional terms, the viola is very much like a violin - it's just a larger version. But how much larger?
Oddly enough, the dimensions of the viola have never been standardised to the same degree as the violin, largely because the true 'optimum' size would be inconveniently heavy and awkward to play. Its strings are tuned a fifth lower than those of a violin: C, G, D and A. If we take the body length of the average violin as 14 inches, this would indicate an ideal viola body of around 21 inches - not the handiest of instruments to play under the chin.
So, inevitably, the design of violas tends to be a compromise between the requirements of acoustics and practicability. A typical body length is about 16 inches, although the well-known 'Tertis' model (pioneered by the outstanding English viola virtuoso Lionel Tertis (1876-1975) is nearer 17 inches in length. 'Full-length' violas have also been constructed, to be played like cellos using an endpin.
The repertoire for the viola as a solo instrument used to be somewhat limited: until recent times, the only significant composition was Berlioz's Harold in Italy, commissioned by Paganini so that he could try out his new Stradivari viola. The first performance of the work was something of a disaster. Paganini had to send a deputy as he was ill and, as Berlioz wryly observed, halfway through the performance the harpist lost her place and the conductor lost his head.
Today, however, the repertoire has been extended through the efforts of a number of contemporary composers. In Germany, Hindemith - himself a viola player - composed many works for the instrument, and it was perhaps appropriate that he should himself be the soloist in the first performance of another great viola work, William Walton's Viola Concerto. Rubbra and Fricker also wrote concertos and Brahms composed some viola sonatas.
For reasons lost in the history of music, viola players have been the butt of the so-called 'viola joke' of which many thousands must now be in circulation. The abysmal quality of most of these jokes may be judged by the following three examples taken from the 'quality' end of the genre:
Q. What is the difference between a front-desk viola player and a back-desk viola player?
A. About a semitone.
Q. Please, would you like to contribute £10 to bury a poor viola player?
A. Here's £100, Bury ten of 'em!
Q. How did the viola audition go?
A. Terrible! I had to enter the room and find the music from memory!
It says a lot for the stoicism of the viola player that jokes like these have been borne with such dignity for so many years. But there are signs that violists are starting to fight back:
Q. Why are viola jokes always so short?
A. So that the rest of the orchestra can understand them . . .
It will come as no surprise that there is a website devoted to The Viola Joke.