This puts men on their mettle. All guesswork is eliminated. Every

mistake is conspicuous. One quickly loses his conceit by learning how often his judgment errs – often nine times in ten.

There one learns that advertising must be done on a scientific

basis to have any fair chance of success. And he learns that every

wasted dollar adds to the cost of results. Here is a tough efficiency

and economy under a master who can’t be fooled. Then, and only

then, is he apt to apply the same principles and keys to all advertising.

A man was selling a five-dollar article. The replies from his ad

cost him 85 cents. Another man submitted an ad which he thought

better. The replies cost $14.20 each. Another man submitted an ad which for two years brought replies at an average of 41 cents each. Consider the difference on 250,000 replies per year. Think how valuable was the man who cut the cost in two. Think what it would have meant to continue that $14.20 ad without any key on returns. Yet there are thousands of advertisers who do just that.

They spend large sums on a guess. And they are doing what that man did – paying for sales from 2 to 35 times what they need cost. A study of mail order advertising reveals many things worth learning. It is a prime subject for study. In the first place, if continued, you know what pays. It is therefore good advertising as applied to that line.