chapter20.txt

CHAPTER XX







EDISON PORTLAND CEMENT







NEW developments in recent years have been more



striking than the general adoption of cement



for structural purposes of all kinds in the United



States; or than the increase in its manufacture here.



As a material for the construction of office buildings,



factories, and dwellings, it has lately enjoyed an



extraordinary vogue; yet every indication is



confirmatory of the belief that such use has barely begun.



Various reasons may be cited, such as the growing



scarcity of wood, once the favorite building material



in many parts of the country, and the increasing dearness



of brick and stone. The fact remains, indisputable,



and demonstrated flatly by the statistics



of production. In 1902 the American output of



cement was placed at about 21,000,000 barrels, valued



at over $17,000,000. In 1907 the production is given



as nearly 49,000,000 barrels. Here then is an



industry that doubled in five years. The average rate



of industrial growth in the United States is 10 per



cent. a year, or doubling every ten years. It is a



singular fact that electricity also so far exceeds the



normal rate as to double in value and quantity of



output and investment every five years. There is



perhaps more than ordinary coincidence in the as-



sociation of Edison with two such active departments



of progress.







As a purely manufacturing business the general



cement industry is one of even remote antiquity, and



if Edison had entered into it merely as a commercial



enterprise by following paths already so well



trodden, the fact would hardly have been worthy of



even passing notice. It is not in his nature, however,



to follow a beaten track except in regard to the



recognition of basic principles; so that while the



manufacture of Edison Portland cement embraces the



main essentials and familiar processes of cement-



making, such as crushing, drying, mixing, roasting,



and grinding, his versatility and originality, as



exemplified in the conception and introduction of some



bold and revolutionary methods and devices, have



resulted in raising his plant from the position of an



outsider to the rank of the fifth largest producer in



the United States, in the short space of five years



after starting to manufacture.







Long before his advent in cement production,



Edison had held very pronounced views on the value



of that material as the one which would obtain largely



for future building purposes on account of its stability.



More than twenty-five years ago one of the writers of



this narrative heard him remark during a discussion



on ancient buildings: "Wood will rot, stone will chip



and crumble, bricks disintegrate, but a cement and



iron structure is apparently indestructible. Look at



some of the old Roman baths. They are as solid as



when they were built." With such convictions, and



the vast fund of practical knowledge and experience



he had gained at Edison in the crushing and manipulation



of large masses of magnetic iron ore during the



preceding nine years, it is not surprising that on that



homeward railway journey, mentioned at the close



of the preceding chapter, he should have decided to



go into the manufacture of cement, especially in view



of the enormous growth of its use for structural purposes



during recent times.







The field being a new one to him, Edison followed



his usual course of reading up every page of



authoritative literature on the subject, and seeking



information from all quarters. In the mean time,



while he was busy also with his new storage battery,



Mr. Mallory, who had been hard at work on the



cement plan, announced that he had completed



arrangements for organizing a company with sufficient



financial backing to carry on the business; concluding



with the remark that it was now time to engage



engineers to lay out the plant. Edison replied



that he intended to do that himself, and invited Mr.



Mallory to go with him to one of the draughting-



rooms on an upper floor of the laboratory.







Here he placed a large sheet of paper on a draughting-



table, and immediately began to draw out a plan



of the proposed works, continuing all day and away



into the evening, when he finished; thus completing



within the twenty-four hours the full lay-out of the



entire plant as it was subsequently installed, and as



it has substantially remained in practical use to this



time. It will be granted that this was a remarkable



engineering feat, especially in view of the fact that



Edison was then a new-comer in the cement busi-



ness, and also that if the plant were to be rebuilt



to-day, no vital change would be desirable or



necessary. In that one day's planning every part



was considered and provided for, from the crusher to



the packing-house. From one end to the other, the



distance over which the plant stretches in length is



about half a mile, and through the various buildings



spread over this space there passes, automatically,



in course of treatment, a vast quantity of material



resulting in the production of upward of two and a



quarter million pounds of finished cement every



twenty-four hours, seven days in the week.







In that one day's designing provision was made not



only for all important parts, but minor details, such,



for instance, as the carrying of all steam, water, and



air pipes, and electrical conductors in a large subway



running from one end of the plant to the other; and,



an oiling system for the entire works. This latter



deserves special mention, not only because of its



arrangement for thorough lubrication, but also on



account of the resultant economy affecting the cost



of manufacture.







Edison has strong convictions on the liberal



use of lubricants, but argued that in the ordinary



oiling of machinery there is great waste, while much



dirt is conveyed into the bearings. He therefore



planned a system by which the ten thousand bearings



in the plant are oiled automatically; requiring the



services of only two men for the entire work. This



is accomplished by a central pumping and filtering



plant and the return of the oil from all parts of the



works by gravity. Every bearing is made dust-



proof, and is provided with two interior pipes. One



is above and the other below the bearing. The oil



flows in through the upper pipe, and, after lubricating



the shaft, flows out through the lower pipe back to



the pumping station, where any dirt is filtered out and



the oil returned to circulation. While this system of



oiling is not unique, it was the first instance of its



adaptation on so large and complete a scale, and



illustrates the far-sightedness of his plans.







In connection with the adoption of this lubricating



system there occurred another instance of his knowledge



of materials and intuitive insight into the nature



of things. He thought that too frequent circulation



of a comparatively small quantity of oil would, to



some extent, impair its lubricating qualities, and



requested his assistants to verify this opinion by



consultation with competent authorities. On making



inquiry of the engineers of the Standard Oil Company,



his theory was fully sustained. Hence, provision



was made for carrying a large stock of oil, and



for giving a certain period of rest to that already used.







A keen appreciation of ultimate success in the



production of a fine quality of cement led Edison to



provide very carefully in his original scheme for those



details that he foresaw would become requisite--such,



for instance, as ample stock capacity for raw materials



and their automatic delivery in the various stages of



manufacture, as well as mixing, weighing, and frequent



sampling and analyzing during the progress



through the mills. This provision even included the



details of the packing-house, and his perspicacity in



this case is well sustained from the fact that nine



years afterward, in anticipation of building an additional



packing-house, the company sent a representative



to different parts of the country to examine



the systems used by manufacturers in the packing of



large quantities of various staple commodities involving



somewhat similar problems, and found that



there was none better than that devised before the



cement plant was started. Hence, the order was



given to build the new packing-house on lines similar



to those of the old one.







Among the many innovations appearing in this



plant are two that stand out in bold relief as



indicating the large scale by which Edison measures



his ideas. One of these consists of the crushing and



grinding machinery, and the other of the long kilns.



In the preceding chapter there has been given a



description of the giant rolls, by means of which great



masses of rock, of which individual pieces may weigh



eight or more tons, are broken and reduced to about



a fourteen-inch size. The economy of this is apparent



when it is considered that in other cement plants



the limit of crushing ability is "one-man size"--that



is, pieces not too large for one man to lift.







The story of the kiln, as told by Mr. Mallory, is



illustrative of Edison's tendency to upset tradition



and make a radical departure from...