THE habit of waste is one of the unfortunate inheritances of the 20th century American Citizen. It is our most serious hinderance to the development of both individual and national efficiency. ore than anything else, it stands in the way of the wise use or conservation of the resources, ample, present and future, supplies of which a Te essential to our individual and national welfare. This fact is important enough to command attention when applied to products of the soil, of which we have new supplies each year; or to our forests ef which each century may bring returns; or to the soils themselves to which the underlying rocks slowly yield new additions as by careless culture we permit the fertile surface to be eroded and carried off to the sea. It is still more important when applied to our mineral resources, of which we have but the one supply-which supply has required millions of years for its accumulation, and which supply at the present increasing rate of consumption may be exhausted while the nation is yet young; and especially' when applied to our fuel resdurces, of which the portions used each day are completely destroyed. And, yet, the very abundance, and supposed abundance, of our mineral resources has developed and encouraged the habit of waste. A legislator of many years' experience in national affairs, was recently. quoted as saying in a public address: “Why, worry ourselves about a future coal supply when there is undiscovered coal enough in the Rocky Mountain regions to warm this nation for a,n indefinite future.” Another of our “older stutesmen” has in recent public utterance' voiced the same view: “We have enough coal and to spare,” he said, “for a thousand decades of our national history; therefore, we need not concern ourselves about the use, nor the waste of American fuel.” And the average citizen has so long heard so much about the -"exhaustless resources” of this country, that he is half way inclined to believe such statements. It is only within the past few years that the real facts of the situation have impressed themselves upon us. The end of the coal supply in certain important centers is found to be already nearly in sight. The cold-blooded statistician studying the. future in the light of the past, tells us that, if the increasing rate of consumption of the past century be continued in the future, our national coal supply may be exhausted within less than two hundred years. The States that frst feel the effect of this fuel exhaustion, in spite of their larger supplies, will be those like Pennsylvania, West Virginia, Ohio, Illinois, and Iowa, located near great manufacturing and transportation centers, and upon whose supplies the largest drains are being made-both in the use and the waste of essential resources. Be this all as it may, as to one fact and principle all thoughtful citizens must agree, namely, that while no one questions the right of each generation to use efficiently of this coal supply all it really needs, this right carries with it a sacred obligation-that no man and no generation of men shall waste that which is not needed for its actual use, and which, therefore, belongs to the nation. Waste in Mining Coal. The fact that the loss of coal in mining operations now approximates 250,000,000 tons per annum; or that we leave underground in such condition as to make its future recovery impracticable, half a ton for every August 12, 1911 SCIENTIFIC AMERICAN 139 tDn of cDal nDW brDught tD the surface, is a fact that cDmmands serious cDnsideratiDn. And what makes a bad matter WDrse, is the fact that this cDal left undergrDund is often a menace tD prDperty by originating Dr harbDring mine fires, and .ften a menace tD life by develDping supplies .f explDsive mine gases that may by falls or settling of rDDf be driven unexpectedly intD the wDrking parts .f the mine, where .pen lights Dr .ther agencies may ignite it and cause a mine disaster_ In some mines frDm eighty tD ninety per cent .f the cDal is brDught to the surface. In many mines the recDvery ranges frDm sixty tD seventy-five per cent .f ,the whDle, while in SDme mines the recDvery is frDm fDrty tD sixty per cent. In SDme cases this lDSS CDnsists mainly .f the pillar coal left in place tD support the rODf while the .ther cDal is being remDved, and which pillar cDal may be later nDt remDved Dr .nly partIally remDved. In additiDn tD this pillar CDa I in many mines there is a “rDDf cDal,” Dr “rDDster cDal,” Dr “tDP cDal,” and also a “bottDm cDal,” which is alSD left underground because lower in quality or more expensive to mine. Additional IDsses .f coal CDming from the pulverizing actiDn of the drills and coal cutting machines (see photo), from the grinding of coal under the wheels of the mine cars (see phDtO); and from the sorting Dr screening and washing and general handling about the shaft and tipple. Much of the fine coal in the mines is nDt removed and remains as a menace to life if involved in dust explosiDns. Much of the fine coal removed from the mines accumulates in the great black piles of culm, where it may Dr may not burn frDm spontaneous fires; or it may be shipped away and marketed as slack; Dr in a few cases this fne cDal is being briquetted and sold at prices as high as thDse .btained for the best lump cDal. All the above sources of waste relate to the losses in mining a single bed .f cDal. Still .ther losses come where several beds of coal occur .ne above the other with thin intervening beds .f rock, from the priDr mining .f the lower bed. This .ften results in an irregular breaking and settling .f the .verlying bed or beds of coal in such a manner as to seriously inter-fere with the subsequent mining and recovery .f this overlying or upper coal. In other countries regulations require in such cases the prior mining .f the overlying Dr upper beds of cDal, in order to avoid this nnneeessary settling and breakage of successive higher beds. But in the United States each company has followed the law .f “present prDfits” and least resistance; and the “future welfare of the natiDn” has remained an irridescent dream. Losses in the Transportation of Coal. From the shaft and the tipple the coal falls into the forty or fifty-ton cDal cars fOT transportation by rail (see photo), or into the barges for transportation by river (see photo). In these transport barges, as seen on the Ohio and Mississippi rivers, a single small stern-wheel steamer attached at the rear of the group .f the barges, may carry tD New Orleans from 40,000 to GO,OOO tons of coal (phOtD) . If intended fDr ocean or lake transportation by steamer, the co,tl may be allDwed tD run from the opening in the bottDm of the car (or an elevajed track) directly into the holJ .f the steamer; or each car may be elevated separately and inverted, thl coal rushing dDwn the chute intD the steamer's hold. At the other termin31 port the cDal whether transpDrted b;{ barge or steamer Is lifted by great steel grab buckets and placed .n stDrage platfDrms (see phDtD) , Dr again placed .n cars fDr further transpDrt (see phDtD). At every handling .f the cDal there is an increase .f fine coal Dr slack (phDtD), and i small per cent of IDSS. But often the tDtal actual waste in the haulage, including the several transfers, will aggregatt less than 10 tD 15 per cent .f the .riginal tDnnage; and while the fine Dr slack cDal sells at prices frDm 20 tD 50 per cent IDwer than the gDDd lump cDal, with modern autDmatic stokers and briquet-ting plants, there is really little lDSS in actual heating value. Losses in the Use of Coal. Great as are the losses .f coal in mining, they are proportionately less than in its burning in the furnace :f the country. The experienced manufacturer who, as a large CDnsumer of eoal, habitually watches the double entries on the pages of his ledger for profits and losses, does not hesitate tD express his surprise and disapprDval when he hears the story of mining losses, approximately 250,000,-000 tons of coal in a single year; but in doing this he often loses sight of the no less serious fact-that of the coal used in his own furnaces, less than 10 per cent of its heat units are convertecl into mechanical work in his factDries; Dr the larger fact, that of the 300,000,000 tons of coal probably used in the power plants of the country (including locomotives), 270,000, 000, * Dr 90 per cent .f the whole, was lost in the several transformations .f energy; and not mDre than 10 per cent of the heat units, Dr the equivalent of only 30,000,000 tDns of this coal, was transformed intD the mechanical work of the natiDn. The situation seems clearer if these .osses are subdivided Dr classified. This cannot be done accurately in f g en eral statement, because of the variations in the different furnaces, boilers and engines. But taking a C0mmon type of smaller power plant, the disposition or cDnsumption of British thermal units in the burning .f the ordinary bituminous coal (containing 13,500 B. T. U.) has been given a,] follows: Per B. T. U_ cent. Loss in ashes......... 135 1.00 Carried off in gases.... 2,970 22.00 Loss in radiatiDn from boilers ............. 675 5.00 Carried off in auxiliary exhaust ....'......... 190 1.41 Loss in radiatiDn and leakage, maiii pipes .. 210 1.5(5 Loss in radiatiDn from ,small pipes.......... 30 0.22 Loss in radiation from engine .............. 280 2.07 REjected to cDndenser .. 7,737 57.31 COl]verted to power Dr mechanical work..... 1,275 9.43 13,500 100.00 ·rhe government .f the United S ta tes is prDbably the world's largest owner of coal lands; it also .perates a large number and variety of heating and power plants located in widely separated parts of the country, beside3 the Panama railroad, lines of transport steamers, and its naval vessels. Furthermore, the fuel prollem enters so' hirgely into the manuJactilring, transportation and interstate CDmmerce of the whcle country that they nIay be reasDnably classed as natiDnal problems.- - :n' recognition' of these facts, Congftss several years ago authorized an investigation- of fuel probJems, first Lnder the Geological Survey, and subSEquently under the Bureau of Mines. LmJer the latter bureau thIs wDrk is now being reorganized, and co-operating with other existing agencIes, the ellgineers and chemists of the Bureau vf Mines, working at its Pittsburg laboratories, are endeavoring tD locate and reduce or eliminate as far as may b8 possible the sources of loss Dr waste not only in the mining, but alsD in the use of .ur fnel reSDurces . (continued on page no 150.) * This does not include ; loss which in extl'Plne casps nY reach 25 per ceut of the coal, where finely dividf'd non-(oking coal passes through tbe grate halS in a n un-burned condition, along wltb the ashes, The Use and Waste of Our Coal Supply (Continued from page no 139.) These problems are intricate, and their satisfactory solution doubtless remote, but they are of such importance as to be worthy of the best efforts of the Government and of its private institutions and individual citizens. In engineering and architecture we hide our ignorance as to the strength and other properties of structural materials behind the well·sounding phraSe, “factors of safety. “ In these important and intricate fuel problems we hide our ignorance and rest our laurels concerning these losses under the equally comforting expression, “transformation of energy.” What Ameriean industry needs is technical information, accurate fundamental data, such as comes from varied, extended, continuous, well directed, and scientific research. Each recent year has witnessed some advance in the line of greater fuel eff-ciency; and while eacn advance has been small, the aggregate has during the past decade raised the percentage of heat units converted into mechanical work from five or six to nine or ten, and slightly more in a few cases. The gas producer and gas engine, the steam turbine, and the improved reciprocating engine, represent steps in this advance. So does also· the development and introduction of the several types of automatic stokers; these latter contributing to efficiency and at the same time lessening the smoke nuisance from modern power plants. These automatic stokers and special grates have further contributed to the conservation of resources by making possible the more efficient burning of fine or slack coal, which formerly was relegated to culm piles as waste, and as such to be burned in the open air. Briquetting is making another contribution along the same line. Another step in the direction of practical eonservation. cleanliness, and hygiene-and one that should be pushed more rapidly-is the location of the great power plants at the mines, and the burning there, e.her in gas producers or specially constructed furnaces, of the low grades of coal now thrown away because they will not bear transportation; and the electric transmission of the power so developed to adjacent cities, towns and isolated plants. I look forward to a time-and it cannot, I believe, be far distant-when ample supplies of electricity so gene.ated and brought into our factories and our homes will not only give us light and power, but will also cook our food and warm our houses. Two other marked advances in the economic utilization of coal deserve mention because of both their extent and their far-reaching importance; one is the large beginning in the manufacture of by.Jrodnct coke for the latest steel plants of the United States Steel Corporation, including the saving of such valuable byproducts as creosote for the preservation of timber, and sulphate of ammonia, so largely used in the fertilizing of crops. The other is the use in large gas engines of the blast furnace gases that formerly were entirely, and in many places are stiI! largely wasted. The losses in these two fields, added to the shameful waste of natural gases, still aggregate year;y from $50,000,000 to $100,000,000; but improvements are under way in all these lines. How These Mining Losses May Be Reduced. No one questions the fact that these losses are real; nor are there any serious differences of opinion as to the proposi-tion that these losses- should be avoided. Just how this best can be done is another matter, and one about which a difference of opinion may naturally arise. . The situation is full of interest; full of problems for the statesman, the engineer and tne economist, the consumer and the producer. It involves the very essence, the purpose and the practicability of the movement for the conservatIOn of resources. The case may be stated as follows: We have but the one supply of coal, and this supply is essential to both the future and the present welfare of the nation. At the present increasing rate of use and waste of this supply, it will be used and destroyed while the nation is yet in its youth. By mining and using this coal more efficiently, the life of the supply may be extended indefinitely, and both the present and future welfare of the nation time properly safeguarded. The coal operator does not practise wasteful methods by preference. He is, ho\'-ever, operating under a system that encourages and even renders inevitahle these wasteful practices; and for which system the public itself is largely respO!-sible. A Federal statute makes . impossible for the coal producers 1.0 eo-operate or combine with a view to fixing a common or non-competitive price for coal at the mine. The demand for coal during the winter season of each year being much in excess of that during the warmer months, and the entire lack of storag(-) facilities at the mines requires for this cold weather demand a mining capacity much in'excess of that necessary for the summer needs. Under such a system there is constantly in progress a fieroe struggle for business, and a reduction to prices so low that they often fail to eover the actual <ost of production-so low that safe and clean mining is discouraged and even rendered impossibIe. Meanwhile, no two States have similar mining laws for the protection of life and property, nor will any State enact, or enforce, if it enacts, drastic legislative requirements, for if it d{)es it thereby plaees its own mine operators at a serious business disadvantage in the snarp com- petition with operators in other States. The remedy is easily stated, but not easily developed. The cut-throat competition should give place to a reasonable combination under such Federal or uniform State control of prices as would guarantee reasonable returns on mining investments, and require mining practice in which both accident and waste are reduced to an absolute minimum. This regulation and readjustment should be extended so as to include the freight and terminal agents' charges; and if this be properly done, safe and clean mining may be realized without material increase in the cost of coal to the ultimate consumer. If to the American people the doctrine of conservation is a thing of substance and not a dream; if those of us who today are wastefully luxuriating in the abundance of inherited resources, have seriously at heart the rights and the weI· fare of that are to come after us; if we are really in earnest about safe-guarding the lines of the more than a million miners who labor underground for our comfort and welfare, we should enact and enforce, the Federal and State legIslatIOn necessary for the accomplishment of these ends. We should render possible the business-like reorganization of this great basic industry. We should see to it that this underlying economic basis is sound, whether judged from the standpoint of the individual or the nation—from the standpoint of the present or future welfare of the nation. The Vibrations of Metals IT has been contended that solid metals 1 may reveal by their structure the vibra. tions to which they have been subjected. In exp},aining this phenomenon, experiments were made in England to show that a beautiful wave structure can be imparted no the surface of mercury by the vibrations of a tuning-fork, and that even the surface of solid lead which has been subjected to similar vibrations possesses a structure resembling that of a vibrating surface ,of mercury. Mild steel was defined as a “solid solution” of iron and carbon, free from cinders. Metallurgists have doubled the strength of steel as it was lmown in early days. Iodide of nitrogen, a black powder, is one of the most dangerous of all explosives. When dry, the slightest touch will often cause it to explode with great violence. There appears to be a certain rate of vibration wh'ich this compound cannot resist. In experiments to determine the cause of its extreme explosiveness. some damp iodide of nitrogen was rubbed on the strings of a bass viol. It is known that the strings of such an instrument will vibrate when those of a similar instrument, having an equal tension, are played upon. In the present case, after the explosive had become throrough'ly dry upon the strings” another bass viol was brought near and its strings were sounded. At a certain note the iodide of nitrogen on the prepared instrument exploded. It was found that the explosion occurred only when a ralte of vibration of 60 per seGond was eommunicated to the prepared strings. Vibration of the G string caused an explosion, while that of the E string had no effect. The quesUon is often asked, What force least expected does the greatest damage to buildings? One architect's answer to this question may be a surprise to those who do not understand that it is the regularity of vibration that makes it powerful. "I venture to say,” remarked this architect, “that you would never suspect that violin-playing would injure the walls of ,a, building. Yet itt certainly does. There have been instances wihen the walls of stone and brick structures have been seriously damaged by the vibrations of a violin. These cases are, of course, unusual, but the facts are established. "The vibrations of a violin are really serious in their unseen, unbounded force, and when they come with regul:uity, they exercise an influence upon struetures of brick, iron or stone. It follows, of course, that there must have been continuous playing for years to callse the loosening of masonry Or to make iron brittle, but it will do so in time."