The young man who has, or thinks he has, made an invention has need of much sense and sound advice before he puts any appreciable amount of either time or money into his invention, says Irv. in "American Machinist." Otherwise, as soon as he sees he has something which he thinks is to revolutionize the porticular class to which it belongs he rushes off to a patent attorney with a rough model of the device, is assured that no doubt a valuable patent can be secured for the invention, and then begins a series of expenses and disappointments which end in a poorer but wiser young man.

The inventor should not let his invention run away with his common sense. He should look for criticism rather than praise. He should weigh carefully its bad points as well as its good ones. Great blame is laid, and rightly, at the doors of unscrupulous patent attorneys, but the stubborn, bound-to-go-ahead inventor has made it possible for such attorneys to do a thriving business. The attorney who is honest enough to suggest that the invention is patentable, but that the patentable part is so small and easy to get around, that it will be throwing money away to take out a patent, is likely to be looked upon with either suspicion or scorn, and see the patent taken out by some less honest competitor.

The young man who has invented or intends to invent should carefully consider several things. He should confine himself to the class of work with which he is familiar. When he has made one invention he is liable to think that he can take a casual glance at most any line of work and improve upon it, but many have tried it to their sorrow. He should carefully consider whether the device is worth patenting, and not whether the device can be patented. There are several ways of arriving at a fairly accurate answer to this all-important question. In the first place, is the new device an improvement on that which is already on the market? Is it simpler? Is it cheaper? Is it so much better that a buyer would be willing to pay a little extra in the way of a royalty over the old device? Let the inventor put these questions to himself, weigh them carefully, and answer truthfully. But even if he can say yes to these questions or to most of them, let him not be satisfied with that. It is essential that he should next find out what others have done along the same line. This is not so difficult as it may seem. For the sum of ten cents he can obtain from the Patent Office a copy of the Classifications of Inventions, giving all the classes and subclasses into which the United State patents are divided. Having ascertained the sub-class in which the device would be classed, let him write and find out the cost for one copy of each patent contained therein. If the cost • is not great he should get them by all mean3. He may find the same thing or a dozen better, and be saved the expense and disappointment of going ahead blindly and obtaining a patent at considerable cost which will be as easy to get around as falling off a log.

The best way of all, is for him to first buy the patent papers and study them carefully. Then let him improve on what he finds there. If he cannot improve on what he finds there, he will do well not to go ahead with a vague idea that in some unaccountable way, to be revealed in the hereafter, the sound-headed business man is going to pick out and adopt the invention disclosed in his patent even though it isn't quite so good as some old patent which can be used without any payment of royalty.