To intelligently and successfully estimate the cost of plumbing work requires more than a mere knowledge of the construction of buildings, the ability to read plans and the skill to take off quantities from the drawings submitted. The real estimator's work does not stop when he has made up a list of materials which the plans show will be required to complete the work, but he supplements his efforts by determining the best means of assembling the goods, how to ship them, and where and in what condition to buy the goods at the least cost for the quality specified. There is a world of originality and ingenuity required to do this successfully, and, perhaps, this cannot be better explained than by giving a concrete example of business enterprise which, if in the newspaper world, would be known as a "scoop" or "beat." In common with a number of others, the writer at one time estimated on a large Government building in which there were miles upon miles of extra-strong galvanized wrought pipe to be used. At the time of estimating, the price of pipe had just gone up and the market was in an unsettled condition, threatening every minute to go higher. As prices then stood, within a month black iron pipe had advanced about 40 per cent. and the list on galvanized-iron pipe had gone up even more. The list price on galvanized-iron pipe had been made just double that of plain iron pipe, and with equal discounts galvanized-iron pipe was just twice as costly as plain iron pipe, notwithstanding that the cost of galvanizing was but a fraction of the cost of the pipe. That was the state of affairs when the bids were opened and the work awarded to the lowest bidder, who was some thousands of dollars below the field, and whose bid was less than the estimated cost of the work as calculated by the other competitors. Loss was freely predicted for the successful contractor by his unsuccessful rivals, who were surprised to see him complete the work with apparent profit. Then the secret of his success leaked out. Instead of figuring the cost of his pipe on the basis of the manufacturers' prices he bought the plain iron pipe from the supply houses, made arrangements with a large galvanizing concern to galvanize all the pipe required for the contract at a price which made the cost of extra-strong galvanized iron pipe but a few cents more per foot than the cost of the plain iron pipe. It is just such enterprise and originality which make a success of the plumbing business. To all appearances competitors estimate on exactly the same materials, taking their items and quantities from identical plans and specifications; yet, when all is said' and done, there is always some chance for the resourceful estimator to profit by his superior knowledge and training, to fairly and honestly beat his competitors. That is what he must do in a large percentage of his endeavors to succeed, and to succeed is what he is in business for. It is the volume of profitable business done in a year which counts, and, as prices to all of equal credit are practically the same, the best chance for the success of a contractor lies in his ability to so plan his work, assemble his materials and handle his contracts generally, that his net cost will be less than that of other contractors. The foregoing story is told to emphasize the point that to be a successful estimator and contractor requires more than the clerical ability to take off quantities from a plan. To be really successful the estimator must possess a complete knowledge of materials, be perfectly familiar with prices, know how to lay out work in the most economical yet, at the same time, sanitary way; he must know his locality and be perfectly familiar with the best and cheapest means of shipping; he must be accurate, resourceful and capable of judging what constitutes a fair day's work. In addition he should be industrious, have character, tact, courage, confidence in himself and his work, perseverance, good manners and be well dressed. Last, but most important of all, he must be honest. Dishonest methods and principles might gain a temporary advantage, but a successful career as an estimator and contractor can be founded only on the rock of honesty.

It is not often that the opportunity for a "scoop," like that related of the galvanized-iron pipe, presents itself to the estimator, but a plumbing installation is never estimated on where there is not an opportunity for the display of some originality in design or execution. Indeed, it generally is the estimator who is the most successful in this respect that reaps the reward of his efforts, and it will be the object of the succeeding paragraphs to point out some of the advanced principles of estimating, so that the beginners will know how to approach the task and be on a more equal footing with his more experienced competitors.