The rule of evidence is plain that makes it necessary for the
plaintiff to show where he saw the defendant, what was done, and what
was said or written by the two parties. If the question is as to the
delivery, it is not enough for the plaintiff to say "I delivered the
goods." The court must have proof of the history of the goods. The
driver of the wagon must be called who can testify where he drove,
what package he carried, and what was done with it when he reached the
house.

The whole subject of expert witnesses is not so complicated after all.
They are merely persons of exceptional experience who are allowed to
testify as to something of which they know nothing. They may have
never seen nor heard the facts in dispute but because they have had so
much experience on similar facts they are allowed to say what they
think of facts produced by eye witnesses before the court. As
conclusions and opinions may be various, there is at times a great
variety in experts, and because the very name of experts implies
technicality, there is a feeling in the minds of the jury and the
public, that the testimony of experts will befog by a mass of
non-understandable terms.

The doctor who testified in a case in which the plaintiff suffered a
sore back and had seventy-five dollars damages from the jury is an
example. He said:

"The plaintiff was suffering from traumatic sacro-illiac disease,
traumatic sinovitis of the knee and wrist and from traumatic myositis
of the muscles of the back."