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T H E J O L - R S A L O F I-VD L’STRId L A S D E L V G I S E E R I S G C H E M I S T R Y
tions ozone seems capable of oxidizing some odorous substances so that the odors are diminished or changed, but the change may be in the direction of increasing the disagreeableness of the odor. I n very great concentrations ozone ‘masks’ most odors by its own intensive odor, and possibly by fatigue or anaesthesia of the olfactory epithelium. Certain odors are masked by ozone even in weak concentrations. Is such masking of odors desirable and generally advantageous? We think not. It is probable that the injury to the respiratory tract by ozone in sufficient concentration to act as an effective mask is of greater moment than the deleterious action of most odors. Except in special industrial processes, the unpleasant odor of the inspired air in shops, offices or living rooms is usually a sign that the air needs to b e renewed or changed. Why should we put out of commission the sense organ which aids us in determining whether or not the air is fit to breathe? It seems to us that this is wrong in principle, and that ozone is being used and will be used as a crutch to bolster up poor ventilating systems. Ozone does not make ‘pure air’ any more than strong spices make pure food. “ I n concentrations that appreciably affect man and animals, ozone appears to have uniformly an injurious action. This injurious action is primarily on the respiratory passages-irritation of the sensory nerve endings, and irritation, corrosion and depression of the epithelial cells. The depression of the alveolar epithelium leads to changes in the gaseous exchange in the lungs, and secondarily to changes in the blood, and ozone headache, depression and drowsiness are produced. “Hill and Flack [Proc. Roy. SOL.,82, 404 (1911);Jour. Roy. SOC.Arts., 60, 344 (1912)]point out that ozone gives a certain ‘tang’ to the air, and thus relieves the impurity (temperature and moisture) which is apt to obtain in offices and assembly rooms, This tang is a combined effect of ozone odor and the ozone irritation of the sensory nerves in the respiratory tract. \Ye have seen that this acts (reflexly) on the vascular mechanism and i t may temporarily ‘whip up‘ a fagged brain. But is this ozone tang any more beneficial or any more physiologic than a whiff of smelling-salts or a puff of the cigarette? We recognize that a certain amount of variation in the rate of movement and in the temperature of the air about us aids in maintaining the tonus of the brain, but our ventilation engineers must reproduce the variability of outdoors by actual variations in the air and in the rate of movement of the air in the ventilating systems, and not by adding a poisonous gas to the air. Nor can we accept the suggestion of Hill and Flack that small amounts of ozone may be of therapeutic value in certain diseases of the respiratory tract by reason of the hyperemia following the ozone irritation. The cells injured by ozone are probably more readily invaded by bacteria, and have less than normal power of growth and healing despite the hyperemia. And all bacteria so far studied are much more resistant to ozone than are the cells of the respiratory tract of man and experimental animals. The physiology of ozone points to the conclusion that the use of this poisonous gas as a therapeutic agent is either valueless or injurious.” T h e second article, “ T h e illleged Purification of Air b y t h e Ozone M a c h i n e , ” b y IT’. A. Sawyer, hI.D., Director of t h e Hygienic L a b o r a t o r y of t h e California S t a t e B o a r d of H e a l t h , a n d his co-workers, B e c k w i t h a n d Skolfield, t h o u g h n o t as extensive, is n o less convincing t h a n t h e first. T h e conclusions of t h e s e a u t h o r s a r e q u o t e d also: “The gaseous products of the two well-known ozone machines examined are irritating to the respiratory tract and, in considerable concentration, they will produce edema of the lungs and death in guinea pigs. “A concentration of the gaseous products sufficiently high to kill typhoid bacilli, staphylococci and streptococci, dried on
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glass rods, in the course of several hours, will kill guinea pigs in a shorter time. Therefore these products have no value as bactericides in breathable air. “Because the products of the ozone machines are irritating to the mucous membranes and are probably injurious in other ways, the machines should not be allowed in schools, offices or other places in which people remain for considerable periods of time. “The ozone machines produce gases which mask disagreeable odors of moderate strength. I n this way the machines can conceal faults in ventilation while not correcting them. Because the ozone machine covers unhygienic conditions in the air and a t the same time produces new injurious substances, it cannot properly be classed as a hygienic device.” I t is t o b e h o p e d t h a t t h e results of t h e s e investig a t o r s will receive sufficient publicity t o correct p o p u l a r i d e a s on t h e germicidal a c t i o n of ozone a n d t h a t t h e w o r k will n o t h a v e t o b e r e p e a t e d a s i t h a s been so m a n y t i m e s within t h e l a s t t w e n t y years.
A. hZ. B U S W E L L BUREAU OF MINES COAL ANALYSES G o v e r n m e n t purchasing a g e n t s , designing a n d opera t i n g engineers, a n d t h e fuel d e p a r t m e n t s of i n d u s t r i a l concerns, dealers i n large q u a n t i t i e s of coal, a n d pers o n s i n t e r e s t e d i n t h e distribution and c h a r a c t e r of t h e different coals i n t h e U n i t e d S t a t e s will find valu a b l e i n f o r m a t i o n i n a r e p o r t j u s t issued b y t h e U n i t e d S t a t e s B u r e a u of X i n e s as Bulletiiz 2 2 , e n t i t l e d “ A n a l y ses of Coals i n t h e U n i t e d S t a t e s , with Descriptions of M i n e and Field S a m p l e s Collected b e t w e e n J u l y I , 1 9 0 4 ~a n d J u n e 30, 1910.” T h i s r e p o r t c o n t a i n s t h e analyses of j,OOO samples of coal t a k e n f r o m 1,jOo coal m i n e s a n d prospects s i t u a t e d i n t h e various coal fields of t h e V n i t e d S t a t e s . N o t o n l y all of t h e i m p o r t a n t fields a r e represented, b u t practically all of t h e m o r e i m p o r t a n t mining districts. T h e p u r p o s e of t h e B u r e a u i n compiling a n d p u b lishing t h i s i n f o r m a t i o n is t o present reliable informat i o n regarding t h e chemical composition a n d h e a t i n g v a l u e of t h e coals. T h e samples of coals were collected b y experienced m e n according t o a definite a n d unif o r m s y s t e m , a n d were analyzed u n d e r carefully controlled conditions, so t h a t t h e r e might b e no q u e s t i o n as t o t h e relative m e r i t s of t h e different coals so f a r as t h i s c a n b e d e t e r m i n e d b y chemical analyses a n d d e t e r m i n a t i o n s of h e a t i n g values. A n increasing p r o p o r t i o n of t h e coal c o n s u m e d in t h e power s t a t i o n s a n d t h e larger m a n u f a c t u r i n g p l a n t s of t h e c o u n t r y is now being purchased u n d e r specifications based on chemical analyses a n d calorimetric d e t e r m i n a t i o n s of h e a t units. I n t h e purchase of fuels m a n y m a t t e r s f o r m e r l y left t o chance a r e now carefully investigated. It is t h e a i m of mechanical engineers t o c o n s t r u c t furnaces a n d t o a r r a n g e t h e h e a t absorbing surface i n a f u r n a c e with reference t o t h e peculiar c h a r a c t e r of t h e fuel which is t o b e b u r n e d . N o t i n g t h e composition of t h e fuel a n d constructing t h e f u r n a c e with reference t o i t , h e c a n assure efficient a n d smokeless c o m b u s t i o n . Moreover, i n a n y p a r ticular m a r k e t , t h e choice of coal is limited generally b y i t s q u a l i t y a n d b y freight r a t e s t o one o r t w o fields i n which t h e c h a r a c t e r of t h e coal beds is c o m p a r a t i v e l y uniform. H a v i n g o n h a n d a representative analysis
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T H E J O U R S A L O F IAVDLTSTRI.4L A X D E Y G I N E E R I ~ V GC H E M I S T R Y
of t h e coal f r o m a given b e d in a n y particular district, t h e engineer can determine whether t h e coal he receives comes f r o m t h e bed a n d t h e district s t a t e d , a n d whether i t is being prepared for m a r k e t as carefully a s i t should be. Wide variations in t h e compositions a n d h e a t i n g values of t h e coals f r o m different districts a n d f r o m different b e d s m a k e comparable analyses almost indispensable t o engineers having t o install boiler or gas-producer p l a n t s in different cities, as well as t o railroads a n d s t e a m b o a t companies, a n d t o t h e engineers a n d purchasing agents of t h e various d e p a r t m e n t s of t h e United S t a t e s G o v e r n m e n t . T h e Bureau of Mines report is in t w o p a r t s : one gives t h e methods used in collecting a n d analyzing t h e samples a n d t h e results of t h e analyses; t h e other
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COPPERCOVERED ORCOPPERCLADSTEEL‘ METAL MADE BY ALLOYING OR WELDING COPPER AND STEEL By J A M E S OTIS HA\DY
Of t h e metals in c o m m o n use, copper is t h e only one which occurs n a t u r a l l y i n large q u a n t i t i e s i n t h e metallic s t a t e . T h e great native copper deposits of Michigan a r e t h e best illustration TThich could be f o u n d of t h e e x t r a o r d i n a r y resistance of copper t o corrosion. c T h e metals zinc, t i n , a n d lead. which a r e commonly used as protective coatings for iron a n d steel, do n o t occur i n t h e n a t i v e s t a t e a n d do not approach copper in durability under atmospheric conditions. Their use is comparatively modern a n d in t h e case of t i n (now selling a t 4 1 cents per p o u n d ) is commercially possible only because of t h e exceedingly t h i n coat which m a y be p u t on ( 2 lbs. per box means a 0.00012 inch t i n coating). T h e necessity of protecting iron f r o m corrosion a n d t h e desirability of strengthening copper alloys used for primitive tools a n d weapons l e d , a t a v e r y early period, t o t h e use of a combination of a n iron core a n d a bronze covering. Such articles h a v e been f o u n d in t h e ruins of S i m r o u d , a n ancient Assyrian city, a n d a m o n g t h e remains of t h e Swiss Lake Dwellers ( F r i e n d : “Corrosion of I r o n a n d Steel,” page 8). F o r similar reasons, t h e union of iron or steel with copper i n such a m a n n e r a s t o obtain a composite m e t a l retaining unimpaired t h e good qualities of b o t h metals h a s long been a desideratum. 1 I a n y inventors h a v e given their a t t e n t i o n t o t h e difficult problem of securely uniting iron or steel with copper. a n d t h e p a t e n t l i t e r a t u r e of t h e United S t a t e s a n d of E u r o p e a n countries contains m a n y illustrations. chiefly of unworkable or imperfect processes. T h e earliest p a t e n t me h a v e f o u n d m-as one issued t o Poole; of E n g l a n d , in t h e year 1821. Copper or b r a s s was melted i n a shallow cast iron p a n (British P a t e n t 4 j 9 8 of 1821). 1 Paper presented at the 48th meeting of t h e American Chemical Society Rochester, September 8-12. 1913.
SO. I I
gives t h e exact location f r o m which each sample of coal was t a k e n , t o g e t h e r with a description of t h e characteristic features of t h e coal bed a t t h e point of sampling, t h e nominal c a p a c i t y of t h e mine a n d such n o t e s o n t h e p r e p a r a t i o n of t h e coal as might be useful t o consumers. T h e d a t a contained i n these t w o volumes are n o t equalled in scope a n d detail a n d i n value for c o m p a r a t i v e purposes b y t h e figures t h a t h a v e been published b y a n y o t h e r coal-producing c o u n t r y in t h e world. T h e G o v e r n m e n t s of some of these countries h a v e published analyses of coals from different mines a n d f r o m different districts b u t , with few exceptions, t h e samples of coal were n o t collected a n d analyzed under a uniform s y s t e m t h a t would m a k e t h e results comparable in all respects.
ORIGINAL PAPERS
THE MANUFACTURE, PROPERTIES AND USES OF COMPOSITE
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T h e commercial electro-deposition or electroplating of copper o n iron or steel seems t o h a v e s t a r t e d before 1840. in E n g l a n d . T h i s process h a s been used chiefly for t h e production of t h i n coatings, b u t processes h a v e been developed b y Elmore a n d others for making, b y electro-deposition, copper t u b e s of considerable thickness. Such a , process was u n d o u b t e d l y used commercially by t h e manufacturers mho, in t h e y e a r 1883, supplied t o t h e Postal Telegraph Cable C o m p a n y bimetallic wire consisting of a h a r d steel core wire o 1 2 0 inch in diameter s u r r o u n d e d b y a seamless, electro-plated, closely-fitting copper t u b e having approximately 0 . 0 4 2 inch walls. T h e r a t i o of steel t o copper b y weight \\*as a b o u t I : 3 (Figs. I a n d 2). T h e s a m e c o m p a n y used also a compound wire consisting of a steel core wire s u r r o u n d e d first b y a t h i n electro-deposited copper s h e a t h 0.008 inch t h i c k a n d t h e n b y a wrapping of heavier copper with walls 0 . 0 4 4 inch t h i c k (Figs. 3 a n d 4 ) . I n neither t y p e of wire was t h e r e a bond between copper a n d steel other t h a n a close conformation. T h e workmanship was so excellent, however. t h a t samples t a k e n down after 28 years’ exposure in t h e line f r o m New York t o Chicago showed absolutely n o corrosion of t h e steel core. T h e copper s h e a t h s retained t h e dimensions given above. Desire t o solve t h e problem of uniting copper with iron or steel would n a t u r a l l y lead t o a t t e m p t s t o make a weld b y processes analogous t o t h e one successful w i t h iron or mild steel. W h e n , however. heating a n d h a m mering iron a n d copper together failed. even with t h e use of various fluxes, t o produce a weld, i t became a p p a r e n t t h a t t h e problem was a difficult one. I n v e n t o r s tried t o follow established methods for coating one metal with a more fusible one, e . g., t h e coating of iron or steel with zinc, t i n , or tin-lead alloy b y passing t h e former metals, properly cleaned. t h r o u g h b a t h s of t h e melted, fusible metals. T h e high melting point of copper a n d i t s strong t e n d e n c y t o oxidize when melted, offered g r e a t obstacles. Coatings made b y dipping steel i n t o melted copper are always t h i n if t h e steel is h o t , a n d a r e usually imperfectly adherent.
