must be taken that these flavourings are properly _blended_. The
great difficulty in giving directions in cookery-books, and in
understanding them when given, is the insuperable one of avoiding vague
expressions. For instance, suppose we read, "Take two onions, one carrot,
one turnip, and one head of celery,"--what does this mean? It will be
found practically that these directions vary considerably according to the
neighbourhood or part of the country in which we live. For instance, so
much depends upon where we take our head of celery from. Suppose we bought
our head of celery in Bond Street or the Central Arcade in Covent Garden
Market on the one hand, or off a barrow in the Mile End Road on the other.
Again, onions vary so much in size that we cannot draw any hard-and-fast
line between a little pickling onion no bigger than a marble and a Spanish
onion as big as a baby's head. It would be possible to be very precise and
say, "Take so many ounces of celery, or so many pounds of carrot, but
practically we cannot turn the kitchen into a chemist's shop. Cooks,
whether told to use celery in heads or ounces, would act on guess-work just
the same. What are absolutely essential are two things--common sense and
experience.

Again, practically, we must avoid giving too many ingredients. Novices in
the art of cooking are, of course, unable to distinguish between those
vegetables that are absolutely essential and those added to give a slight
extra flavour, but which make very little difference to the soup whether
they are added or not. We are often directed to add a few leaves of
tarragon, or chervil, or a handful of sorrel. Of course, in a large
kitchen, presided over by a Francatelli, these are easily obtainable; but
in ordinary private houses, and in most parts of the country, they are not
only unobtainable but have never even been heard of at the greengrocer's
shop.

In making soups, as a rule, the four vegetables essential are, onion,
celery, carrot and turnip; and we place them in the