From the Library: Hast & Reeves

Sim Reeves (1821-1900)

You will never get a bright tone with a dull face. At the same time it is necessary and advisable to warn students against wearing a perpetual set smile. It kills most of the vowels and stiffens the jaw. Freedom and looseness are equally necessary in both joy and sorrow.  
The space behind the uvula should be wide and gaping, but not stiff. The larynx as low as it can go and loose too (which it will be if the breath is taken correctly). It is unconsciously drawn downwards and forwards in relation to the sense of expansion, and it is adjusted to the needs of every vowel and position. It is drawn up in the guttural consonants K and G.
As the voice ascends in the scale the larynx must not be allowed to rise up, as it will often want to do, but must remain low and loose exactly the same for the high notes as for the low ones. The tongue should lie flat and limp and forward on the floor of the mouth.  The lower jaw should hang quite freely without the smallest feeling of tightness. 
The spaces in the mouth and behind the uvula can by these means be enlarged to their utmost. "Gaping' is the right word.  When you sit on the edge of your bed and revel in your first great morning yawn, your throat is in just the right position for singing.  
The Singer's Art: Letters From A Singing Master by Harry Gregory Hast, 1925, p 13-14 

Hast was a student of Sim Reeves, the great English Tenor who wrote a very interesting book on singing which can be read here.   And Sims?  He studied with Marco Bordogni—a very famous pedagogue and Rossini tenor—of the Paris Conservatoire. Bordogni? He studied with tenors Gaetano Crivelli and Giacomo David of the Bergamo singing school which also produced Giovanni Battista Rubini- the Caruso of his day.

Tenors take note! 

Reading Hast and Reeves illuminates a different time and place.  Reeves words on the Tenor voice—and the use of Head Voice—being of particular significance.