The Delicate Nature of the Human Voice
Of all instruments the human voice is by far the most delicate and the most fragile. The wonder is that it will stand as much "punishment" as is constantly given to it. Some novices seem to treat it with as little respect as though it were made out of brass like a tuba or a trombone. The voice is subject to physical and psychical influences. Every singer knows how acutely all human emotions are reflected in the voice; at the same time all physical ailments are immediately active upon the voice of the singer.
There is a certain freshness or "edge" which may be worn off the voice by ordinary conversation on the day of the concert or the opera. Some singers find it necessary to preserve the voice by refraining from all unnecessary talking prior to singing. Long-continued practice is also very bad. An hour is quite sufficient on the day of the concert. During the first years of study, half an hour a day is often enough practice. More practice should only be done under special conditions and with the direction of a thoroughly competent teacher.
Singing in the open air, when particles of dust are blowing about, is particularly bad. The throat seems to become irritated at once. In my mind tobacco smoke is also extremely injurious to the voice, notwithstanding the fact that some singers apparently resist its effects for years. I once suffered severely from the effects of being in a room filled with tobacco smoke and was unable to sing for at least two months. I also think that it is a bad plan to sing immediately after eating. The peristaltic action of the stomach during the process of digestion is a very pronounced function and anything which might tend to disturb it might affect the general health.
The singer must lead an exceedingly regular life, but the exaggerated privations and excessive care which some singers take are quite unnecessary. The main thing is to determine what is a normal life and then to live as close to this as possible. If you find that some article of diet disagrees with you, remember to avoid that food; for an upset stomach usually results in complete demoralization of the entire vocal system.