W. E. S. TURNER and C. J. PEDDIE-Molecular Association in Aqueous Solution illustrated by Hydroxyl containing Substances. W. E. S. TURNER-The Problem of Molecular Association. I. The Molecular Complexity of the Halogen containing Substances. Dr. J. F. THORPE -An Instance illustrating the Relative Instabilities of the Trimethylene Ring as compared with the Tetramethylene Ring. A. D. MITCHELL and Dr. J. F. THORPE-The Elimination of a Carboxethyl Group during the Closing of the Five Membered Ring. Dr. J. KENNER and E. WITHAM-Formations of Tolane Dr. J. KENNER and Prof. W. P. WYNNE-The Nitro, Dr. F. M. PERKIN-The Action of Metals upon Alcohols. Hydroaromatic Substances. Aromatic Nitroamines. Isomorphous Benzene Derivatives. Dr. F. F. BLACKMAN-The Biochemistry of Respiration. (Discussion). R. BLAIR and Sir W. TILDEN-The Neglect of Science by Prof. ARNOLD-On a Fourth Recalescence in Steel. Prof. H. E. ARMSTRONG-The Provident Use of Coal. Dr. W. ROSENHAIN-The Crystalline Structure of Iron at High Temperatures. Report of the Committee on Electroanalysis. Prof. Sir William Ramsay, K.C.B., F.R.S., has been elected President of the Association for the year 1911-12. The Meeting will be held in Portsmouth from August 30th to September 6th, 1911. two The Chemical Laboratory Fresenius at Wiesbaden. -During the Summer Term, 1910, fifty-two students, including ten ladies, attended the Chemical Laboratory Fresenius. Of these thirty-nine were from Germany, three from France, three from Russia, two from the United States of America, and one each from England, Holland, Roumania, Sweden, and Turkey. There were assistants in the Teaching Laboratory and twenty-seven in the Private Laboratories (Versuchsstationen). To the certified staff of teachers belong the Directors, Geh. Regierungsrat Prof. Dr. H. Fresenius, Prof. Dr. W. Fresenius, Prof. Dr. E. Hintz, and also Dr. L. Grünhut, Dr. R. Fresenius, and J. Huber (Architect). The next Winter Term begins on October 17th. During the Summer Term, 1910, besides the scientific researches, a great number of analyses were undertaken in the different departments of the Laboratory (Versuchsstationen), in the interests of trade, industry, mining, agriculture, hygiene, justice, and government. Condensation of Phenolisoxazolone with Mesoxalic Ether.-André Meyer.-When phenylisoxazolone condenses with mesoxalic ether the colourless crystalline compound obtained has the formula C25H22O8N2, and is the mesoxalate of ethyl-bisphenylisoxazolone. It yields welldefined metallic salts, and from it the author has also prepared the diethyl, diacetyl, and dibenzoyl derivatives.Comptes Rendus, cl., No. 26. MACMILLAN'S NEW and RECENT BOOKS ON CHEMISTRY. Methods Used in the Ex amination of Milk and Dairy Products. By Dr. CHR. BARTHEL. Translation by W. GOODWIN, M.Sc., Ph.D., South-Eastern Agricultural College, Wye, Kent. Illustrated. 8vo. 7s. 6d. net. Theoretical Principles of the Methods of Analytical Che- Practical Chemistry. By JAMES BRUCE, Ph.D., B.Sc., F.I.C., A.R.C.S., and HARRY HARPER, A.R.C.S., Head of the Chemistry Department of the Trade and Grammar School, Keighley. Globe 8vo. 2s. 6d. EDUCATIONAL NEWS.-"We have pleasure in recommending this book not only to students but to teachers of chemistry, and feel certain it will occupy a high place amongst books on like subjects." Crystalline Structure and Chemical Constitution. By A. E. H. TUTTON, M.A., D.Sc. (Oxon.), F.R.S., A.R.C.Sc. (Lond.). 8vo. 5s. net. [Science Monographs. NATURE. "It is a goodly story that he has to tell, and well is it told; without wearying the reader with an unwieldy mass of details, he presents in all essential completeness a vivid picture of an unusually coherent series of investigations. . The book is one that should be read and studied by all interested in crystals, their properties and their formation." FOURTH EDITION, entirely Re-written and Enlarged. Chemical Technology and Analysis of Oils, Fats, and Waxes. NATURE.-"Well maintains its place in the front rank of works devoted to the study of oils, fats, and waxes. To the chemical technologist it is practically indispensable." SECOND EDITION, Revised. A College Text-book of Chemistry. By Prof. I. REMSEN. Second Outlines of Chemistry. A Text-book for College Students. By Professor LOUIS KAHLENBERG, Ph.D. Illustrated. 8vo. 11s. net. MACMILLAN & CO., Ltd., LONDON. CHEMICAL NEWS, Honours conferred upon Scientific Men at Sheffield University. Sept. 23, 1910 THE most brilliant gathering in the history of the University of Sheffield was witnessed in Firth Hall on Tuesday, the 6th, when a Degree Congregation was held in honour of the visit of the British Association to the City of Steel. Sitting on the throne in the centre of a raised dais was the Chancellor of the University (the Duke of Norfolk), robed in black velvet and golden braid. Earl Fitzwilliam in scarlet robe was seated immediately to his right, and next him the Rev. Prof. Bonney. To the left were seated the Pro-Chancellors (Mr. George Franklin and Mr. H. K. Stephenson). All eyes, however, were concentrated on the group of savants, robed in brilliantly coloured doctor's robes, who sat in the body of the hall near the throne waiting to be called to occupy posts of honour left vacant for them on the front of the dais. The Public Orator (Prof. Appleton) stepped forward to the front of the throne as each recipient of honour in rotation advanced to the throne and raised his hat in compliment. Then, facing the Chancellor, he delivered a well-thought-out oration which might have done credit to a Demosthenes, so that the world might know whom Sheffield sought to honour. Degrees were conferred as follows: Doctor of Science Thomas George Bonney, F.R.S. Sir William Crookes, O.M., F.R.S. Thomas William Rhys David, F.R.S. Doctor of Engineering— Sir Joseph Jonas (Sheffield). Sir William Henry White, F.R.S. Doctor of Metallurgy — John Edward Stead, F.R.S. 151 secrets of some of the most difficult of the rocks of Britain, but he has devoted special attention to the crystalline schists of the Alps, and has traced the diamond to its home in the eclogite of South Africa. In less specialised fields he has investigated many problems of physical geology-the action of glaciers, the formation of lake basins, the nature and origin of volcanoes, and the conditions of the formation of triassic rocks; and in addition to all this mass of scientific work he has found time to write many volumes of a more literary character which have made his name familiar to many to whom pure science is a sealed book." MR. WILLIAM BATESON "May almost be called the founder of an entirely new He was the first scientist school of Biological research. to make a serious attempt to show the real bearing of the principle of discontinuity in variation upon the problem of evolution; and he was the first Englishman to recognise the true import of the almost forgotten theory of heredity that was put forward a generation ago by the Austrian monk Mendel. Mr. Bateson and his coadjutors have succeeded in accumulating a mass of experimental evidence of the truth of Mendel's law, and have thereby probably placed us on the threshold of a new epoch in our knowledge of organic evolution." SIR WILLIAM CROOKES "May be said to have devoted his whole life to scientific investigation purely and simply for investigation's sake. It is nearly fifty years ago that he discovered a new element, Thallium, and since then he has built up for himself a great reputation in many branches of chemistry and physics. His work in connection with high vacua and radiant matter was epoch-making in its importance, and his more recent work as a pioneer in the separation and determination of the rare earths is specially remarkable for the accuracy, the acuteness of observation, the dogged persistence and unwearying patience for which he has always been noted as an investigator." DR. DARWIN "Is the distinguished son of a world-famed father, one who has earned quite remarkable distinction both in the world of letters and in the world of science. His writings upon the life and letters of Charles Darwin display literary gifts of a high order, while in his botanical work he has not only developed certain lines of his father's work in connection with the study of the sensitiveness and movements of plants, but he has also, by means of new apparatus of the most ingenious and delicate kind, observed the process by which water is given off from the leaves of plants and the method by which such loss of water is controlled by plants." PROF. RHYS DAVIDS "Is recognised at home and abroad as the greatest living authority upon Pali-the sacred language of Buddhism -and upon Buddhist literature generally. He is the founder Prof. Appleton, who presented the recipients of Degrees and president of the Pali Text Society, for which he has to the Chancellor, said: Dr. BONNEY. "The distinguished attainments of the Rev. Prof. Bonney are by this time almost as familiar to the ordinary citizen of Sheffield as they have long been to the members of that famous Association of which he is this year the President. It is in that capacity that this University to-day delights to honour him; at the same time she honours herself by placing on the roll of her honorary graduates the name of one who has long held rank among the leading geologists of the world. It is specially appropriate that the University which the late Dr. Sorby did so much to found should confer the highest distinction in its power upon a scientist who has so materially contributed to that study of microscopical petrology of which Dr. Sorby was the father. Not only has Dr. Bonney unravelled the structuraj edited several of the sixty-five volumes already published. Prof. Davids is the great authority also upon the history and general condition of India during the early centuries of Buddhism, and holds a very high place among the students of early religions generally." SIR ARCHIBALD GEIKIE "Stands in the very first rank of modern geologistsdistinguished at once for the quantity and the diversity of his original research, for the great extent of his field experience, and also for the number and the excellence of the educational works by which he has so materially contributed to the advancement and the diffusion of geological knowledge. His works upon Scottish scenery, upon volcanoes and volcanic action, upon the old red sandstone have long been rated, each in its special line, 152 Honours conferred upon Scientific Men at Sheffield University. CHEMICAL NEWS, Sept. 23, 1910 among the classics of geological literature; and his power | element, helium, which he has more recently proved to be of clothing the bare facts of science in the most fascinating literary garb has gained for him readers and students wherever the English language is spoken. In the most remarkable degree he has combined the function of an original investigator with that of a most attractive and persuasive teacher." PROF. HOBSON. .. The name of Prof. Hobson is familiar to all mathematicians. From his early work in the lowly regions of applied mathematics, he has more recently soared into the dizzy altitudes of the highest and purest mathematicswhere few indeed can follow him. Transfinite numbersnumbers which transcend all finite ideas-are Prof. Hobson's playthings; and it is whispered that he has clear ideas of a series of numbers which transcend in magnitude all transfinite numbers to as infinite extent as the transfinite numbers transcend those of everyday life. He has great influence with the younger mathematicians of his own and of other universities, and played an important part in the remodelling of the mathematical tripos at Cambridge." SIR NORMAN LOCKYER. "The reputation of Sir Norman Lockyer rests upon many and varied grounds. Among other results of a lifetime devoted to the study of solar physics he was one of the first to render possible the detection and observation of the solar prominence otherwise than at a time of total eclipse; by his prolonged study of the periodic changes in the sun's spectral lines he has made enormous additions to our knowledge of solar spectroscopy, and of late years he has turned his knowledge of the sun and the stars to help in the solution of some of the problems of archæology." SIR OLIVER Lodge. "Sir Oliver Lodge bears a name familiar to all members of this congregation and to most of the world outside it. Among physicists his work on the relations between matter and ether has long been recognised as of outstanding value; and it is a well known fact that, working deliberately upon Maxwell's theory of electro-magnetic field, he obtained almost simultaneously with Prof. Hertz experimental evidence of what we now know to be the basis upon which the whole theory of wireless telegraphy rests. To the world at large Sir Oliver Lodge is noted for the breadth and diversity of his interests and the vitalising force of his personality. To the world of education, as the first principal of the University of Birmingham, he has shown what enthusiasm and determination can do to win popular recognition for the highest University learning in a modern industrial centre." DR. MIERS. "Dr. Miers is one of those who has contributed largely to the progress which has recently been made in our knowledge of crystallography-especially in his papers on the variation of angles observed in crystals and upon the spontaneous crystallisation of the substances which form a continuous series of mixed crystals. As Waynflete Professor of Mineralogy at Oxford, he did much towards the foundation of a mineralogical school at that University, and his "Introduction to the Scientific Study of Minerals" is likely to remain a classical authority on the subject to which he has devoted the greater part of his life." SIR WILLIAM RAMSAY. "Sir William Ramsay has long since proved himself a most brilliant and original investigator in connection with that important group of subjects which lies on the borderland between physics and chemistry. Since the world-famous researches into the properties of Argon, which he conducted in collaboration with Lord Rayleigh, he has had a series of scientific triumphs. He discovered many years ago the existence as a terrestrial substance of that new one of the products of the disintegration of the mysterious substance, radium. By a series of the most delicate experiments he has also succeeded in isolating from the air a complete group of new elements, entirely devoid of chemical properties, and has achieved the unique distinction of adding, not one element merely, but an entire group of Mendeleeff's Periodic Table." PROF. SHERRINGTON. "Prof. Sherrington is honoured among physiologists at home and abroad for the original work he has done especially in connection with the brain and the nervous system. He is a most indefatigable and penetrating student of the intricacies and function within that system, and has added very materially to our knowledge of all the structures and processes that are associated with the activities of the mind." SIR JOSEPH THOMSON. "The name of Sir Joseph Thomson must take a very high place even in this distinguished company of scientists. Both in the region of pure theory and in that of experi mental work he has long held an almost unique position; in both cases mainly in that interesting and important department of scientific knowledge which belongs partly to physics and partly to chemistry. His own work has thrown a flood of light, derived from many sources, upon the nature and the constitution of matter, and his laboratory has been and is the inspiration and the training ground of fields of research that have been opened up by the study a host of young investigators, especially in those great of the conduction of electricity through gases for which he has done so much." SIR JOSEPH JONAS. "Sir Joseph Jonas has long been a familiar figure in the civic and educational life of this city, and it would be difficult to over-estimate his services in either capacity. As Lord Mayor he took a leading part in the management of this University; as vice-chairman of the Committee of the Applied Science Department he has exercised a controlling influence over this most important branch of our educational system, and as acting chief of a firm which represents a leading Sheffield industry, he has exemplified in a most striking manner the results which may be attained by the association of pure science with industrial practice." SIR WILLIAM WHITE. "To the world of marine engineers the name of Sir William White is the name of names, and nowhere is it held in greater reverence than here in Sheffield. He may fairly be called the father of the modern fighting ship; he has done for the world's navies what Brunel did for its mercantile marine, and of such vital importance were the services he rendered to our navy during the years when he was responsible for the design of each of its units, that Parliament acknowledged them by special act and grant. The principles of naval architecture laid down by him have been adopted in every shipbuilding yard in the world, and his pupils have covered the great waters with the copies or the developments of his designs." Mr. J. E. STEAD. “Mr. J. E. Stead is universally recognised as one of the leading authorities upon metallurgical subjects. He has contributed largely to the expansion of the science of metallography, and has probed deeply into the different problems which arise out of the study of the crystallisation of iron. His researches into the relationships between iron and phosphorus are amongst the acknowledged classics of the metallurgy of iron and steel. For the University of this City of Sheffield it is a peculiar pleasure to honour one so distinguished in connection with the science to which her own industries are so greatly indebted." The President of the British Association (Prof. Bonney), | open chain nitriles, because it has been found that the responded at the close of the ceremony, thanked the Chancellor for the great honour conferred upon his colleagues and himself, and of which they were keenly sensible. He thanked the University for the leading part it had taken in welcoming the British Association to the city and for the admirable arrangements in which it had co-operated. Sir Oliver Lodge, in replying, made reference to the absence from the congregation of the Vice-Chancellor (Sir Charles Elliot), who met with a motor accident just over a week ago, and expressed much regret on that account. Remarking that he was present at the last visit of the Association to Sheffield, in 1879, Sir Oliver said that the advancement and improvements in the city were very notable, especially to an outsider who, like himself, had not seen much of the place in the time which had since elapsed. He recalled that on that occasion Sir William Crookes, the veteran now happily with them, brought forward in a great lecture what was practically the discovery of the cathode rays, a discovery which underlay and was the precursor of radio-activity, and of the great progress which had been going on in late years, and which some of them more or less knew about. The pioneer work of the phenomena of vacuum-tubes we owed also to Sir William Crookes and the great lecture in Sheffield in 1879. There had since been an upward march, and the university laboratory had delivered up its secrets to pertinacious investigators, and now there was a time ahead-for which that University stood—of earnest spirit and open mind. THE author described some results recently obtained by him in a critical study of the spectral series of the second and third groups of the Periodic Table of Elements, more especially their dependence on the atomic volume of the element. Formulæ constants obtained from the wavenumbers of three lines of the Sharp series are definite functions of atomic weight and atomic volume. The exact form of the function of atomic weight had not been yet determined, but when it is known the measurement of the wave-lengths of a spectrum should give one of the most accurate methods of determining the atomic weight of an element. The function of the atomic volume was so far determined as to give deductions of atomic volume, or of density, very close to observational values in the case of the first three groups of the Periodic series. Applying the method to the spectrum of europium as given by Exner and Haschek, a density of 13'1 was predicted for that element. AN INSTANCE ILLUSTRATING THE RELATIVE THE instability of a ring of three carbon atoms, they said, is illustrated by the fact that certain compounds of this type behave as aß-unsaturated ethyl salts, and readily form condensation products with substances of the type of ethyl malonate. The process of forming condensation products in this manner has been used for the formation of Abstract of a Paper read before the British Association (Section A), Sheffield Meeting, 1910. + Abstract of a Paper read before the British Association (Section B), Sheffield Meeting, 1910. nitriles produced in this manner readily pass into imino derivatives of cyclopentane. An attempt was therefore made to apply this reaction to the corresponding derivatives of the four carbon ring in order to find if the open chain nitrile produced in this manner would pass into the corresponding derivative of cyclohexane. It was found that the four carbon rings remain under the experimental conditions employed entirely unaffected, but that a condensation product isomeric with that desired was produced by the formation of an imino compound with the nitrile group of the ring. It was also found that derivatives of the trimethylene ring, having two carbethoxyl groups on different carbon atoms, also formed condensation products, but that the cis modifications of these ethyl salts appeared to enter into condensation much more readily than the isomeric trans modifications. These condensation products pass at once into derivatives of cyclopentane, but, owing to the fact that the open chain compounds have no more than one carbethoxyl group attached to any carbon atom ring, formation is effected without the production of ethyl carbonate. THE ELIMINATION OF A CARBETHOXYL GROUP DURING THE CLOSING OF THE Five membERED RING.* By A D. MITCHELL and Dr. J. F. THORPE, F.R.S. It was shown that the closing of an open chain of five carbon atoms to form a five-membered ring imparts to the molecule a condition of tension which limits the capacity of the constituent carbon atoms of combining with groups of more than a certain volume. Thus the closing of the five ring to form the two hydrindones or their derivatives necessitates, in the first instance, the freeing of the carbon atoms constituting the rings from these groups of high molecular volume, otherwise the closing of the ring does not ensue. The actual instances dealt with in the present experiments were those derived from a-hydrindone, and it was shown that when the open chain nitrile, from which this substance can be derived, contains two carbethoxyl groups on the same carbon atom, one of these groups is quantitatively eliminated as ethyl carbonate before the closing of the ring. The carbethoxyl group is also eliminated in like manner if a nitrile group and a carbethoxyl group are attached to the same carbon atom of the open chain nitrile, whilst if an acetyl group and a carbethoxyl group are attached to one carbon atom the acetyl group is completely eliminated as ethyl acetate prior to the closing of the ring. ALLOTROPY OR TRANSMUTATION?† By Prof. HENRY M. HOWE, LL.D. IF after defining "elements" as substances hitherto indivisible, and different elements as those which differ in at least some one property, and after asserting that the elements cannot be transmuted into each other, we are confronted with the change from diamond into lampblack, and with the facts, first, that each is clearly indivisible hitherto and hence an element, and, second, that they differ in every property, we try to escape in a circle by saying that they are not different elements because they do change into each other. In short, we limit the name "element 99 to indivisible substances which cannot be transmuted into each other, and we define those which do transmute as ipso facto one element, and then we say * Abstract of a Paper read before the British Association (Section B), Sheffield Meeting, 1910. + A Paper read before the British Association (Section B), Sheffield Meeting, 1910. that the elements cannot be transmuted. Is not this very like saying that, if you call a calf's tail a leg, then a calf has five legs? And if it is just to reply that calling a tail a leg does not make it a leg, is it not equally just to reply that calling two transmutable elements one element does not make them so? Is it philosophical to point to the fact that two such transinutable elements yield but a single line of derivatives as proof that they are one element? Is not this rather proof of the readiness, indeed irresistibleness, of their transmutation? Does not this simply mean that the derivativeless element, whenever it enters into combination, inevitably transmutes into its mate which has derivatives ? We have become so accustomed to the present point of view that it seems to us second nature; but if we look frankly at it, is it a tenable or philosophical point of view? This question is not without a practical application. If, instead of saying "The elements cannot be transmuted into each other," we were to say "Hitherto no elements have been transmuted into each other except those which transmute so readily that the derivatives of only one of them have been recognised," we should take a point of view from which the transmutation of, say, copper into lithium ceases to be so improbable antecedently as to call for extraordinarily conclusive evidence. THE CLOSING AND WELDING OF BLOWHOLES IN STEEL INGOTS.* By Prof. HENRY M. HOWE, LL.D. IN the solidification of molten or liquid substances, especially those of high melting-point, two classes of cavities are likely to form: gas bubbles called " "blowholes," and a central contraction cavity called a "pipe." The blowholes represent (a) the progressive concentration in the molten or liquid mother mass of the gases initially present, a concentration carried on to supersaturation, and to the liberation of part of this gas from the supersaturated layers; and perhaps (b) in some cases, such as that of the solidification of steel ingots, the formation of a gas from chemical reaction brought about by fall of temperature or by passage from the liquid to the solid state. In the case of steel ingots there are indications that carbonic oxide is thus formed during solidification by the union of carbon and oxygen present side by side in the molten metal. The formation of the central " 'pipe" is due to the cooling, and hence contraction of the different layers of the mass æoliotachically, i.e., at different rates inter se. In the first stages of solidification the outside of the mass, especially if it is cast in a cold iror. mould, cools much faster than the still molten interior. The early excess of contraction of the outside, caused by this excess of cooling, is resisted by the lagging interior, with the result that the outer layers are virtually stretched beyond their normal dimensions, so that when solidification is complete the interior, which in the latter part of the cooling has to cool through a greater range of temperature and hence has to contract more than the outside, no longer suffices to fill that outside completely, and this deficit of volume of the interior is represented by a central cavity overlying the region in which the last of the solidification occurs. This same excess of contraction of the earth's crust in its early stages should later throw that crust into great compression, which may be an important element in volcanic and earthquake phenomena. Blowholes themselves tend in effect to expand the volume of the interior as a whole without changing its outer dimensions and thus to lessen the deficit or pipe. A Paper read before the British Association (Section B) Sheffield Meeting, 1919, In case of steel ingots this pipe may reach very deep into the axis, and, because it is hard to work up, may compel us to disregard as much as one-third of the ingot in order to get sound unpiped metal. To avoid this some makers of steel of a composition favourable to welding have purposely allowed blowholes to form rather abundantly, so as to prevent the formation of a pipe, and, relying on the ease with which such steel welds, have tried to get flawless metal by welding these blowholes up in the process of rolling the ingot out into its final form, such as that of a boiler plate. This procedure is of great economic importance, in that it enables the steel-maker to avoid the serious discarding which would be necessary in case his ingots were free from blowholes and hence deeply piped. But many intelligent metallurgists have condemned this practice on the ground that the closing of blowholes is impossible, because the gas which they contain must remain ever present during the rolling, even though somewhat compressed. In some late investigations I have carried out two lines of inquiry as to whether the gas of the blowholes is qualitatively absorbable and whether the sides of the blowholes themselves are qualitatively weldable under the conditions of actual manufacture. Both lines proceed by comparing the metal in slabs cut from the original ingot without rolling, with metal cut from a boiler plate into which that same ingot was rolled, and cut in such a way as to separate and distinguish those parts of the metal in the plate which had originally been porous when in the ingot from those which had originally been compact. The first line showed that the enormous differences in density which existed between the porous and the compact parts of the ingot were practically completely obliterated in rolling the metal down into a boiler plate. In one case the initial difference of 16 per cent in density was completely removed; in the other the initial difference of 10 per cent in density was reduced to one-fiftieth its original quantity. This tended strongly to confirm the strong antecedent probability that the blowhole gases could be reabsorbed during the rolling process, thanks to its high temperature and pressure. The second line of enquiry disclosed what traces of blowholes remained in the boiler plate by cutting very thin slices lengthwise and crosswise from that plate, mirrorpolishing them, and then bending them double in such a way that any blowhole traces present ought to gape open like the cards of a bent pack. Had there been no welding of blowholes this bending should have disclosed unwelded seams about 3.5 inches long and 1.3 inches wide. In point of fact the traces detected were so short as to indicate strongly that a very great degree of welding had occurred. It had seemed to me extremely probable, antecedently, that such welding ought to occur; but here some very competent writers had differed with me. The longest single trace was 0.7 inch long. Only one important 'string" of such traces was found, and this was only 0.3 inch long. Further, the scantiness of these relics of blowholes tends to show that the blowhole gases have been re-absorbed by the metal to a very great degree. I suggest that such relics of blowholes as have persisted represent in most cases spots where the re-absorption of the gas has become complete after the temperature has fallen too low to permit welding. I therefore suggest prolonging the exposure to a temperature above the welding-point, so as to complete the re-absorption of gas while the metal is still weldable. of the blowholes ought to be promoted rather by the The re-absorption of the blowhole gases and the welding practice of "re-heating" than by that of "direct rolling." In the former the ingot is rolled part way towards its final shape, and the resultant "bloom" is then re-heated before further rolling; in the latter the ingot is rolled to its final shape, such as a rail or a boiler plate, at a single heat. During the early part of the rolling the metal surrounding each blowhole should become strongly charged with gas |