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Report of the Board of Commissioners of the Geological Survey of Pennsylvania to the Legislature, January 1, 1887
232 THE F L O W
The #'low of Metals. OF M E T A L S
IN THE D R A W I N G
[J. F. I., PROCESS.
ADDENDUM.
IN MR. OBERLIN SMITH'S LECTURE upon the "Flow of Metals," etc., upon page 23 of the JOURNALfor November, I886, equation (5) should read 2 ( / + r ' ) - - 2 e ~--- r - - instead of with the sign of equality after the first 2, as the printer made it to read. To make clearer the derivation of equation (3), it m a y be said that therein the value x has been found for sharp cornered work, w h o s e " c o n t o u r " is, of course, its diameter plus twice its height. In equation (6) the value x is decreased by r - because its contour is that much less, by the amount r __ at each corner, as shown in 2 equation (4). This assumes that there is no radial stretch in arc e, due to the " drawing" action. Practically this is nearly true for corners of small radius, but not for large ones, as explained in the previous paragraph. BOOK
NOTICES.
REPORT OF THE BOARD OF COMMISSIONERS OF THE GEOLOGICAL SURVEY OF PENNSYLVANIA TO THE LEGISLATURE, J a n u a r y I, I887. This small p a m p h l e t of six pages contains two small maps of the state, colored to represent the counties of which geological reports h a v e been published, a n d the counties of which colored geological maps h a v e b e e n published. It" gives a list of the work done in the field a n d by the printing-press during the last two years, a n d specifies fifteen odd jobs throughout the state which r e m a i n to b e done. A m o n g them, is " a detailed mineralogical s u r v e y " of the South Mountain, in Cumberland, York, F r a n k l i n a n d A d a m s Counties, " for whic.,k we h a v e a perfect m a p basis." This m a p basis (doubtless L e h m a n ' s contoured m a p of the South Mountain) will prove a very important addition to the survey's records, but it was not k n o w n before this a n n o u n c e m e n t that it was completed. A " m i n e r a l o g i c a l s u r v e y " is one of those singularly u n h a p p y expressions which, like h u m a n society in travail,' voices a w a n t for which itself c a n n o t find words ;' or, at least, the right ones. However interesting a mineralogical survey, or a search for minerals m i g h t be, a work more in keeping with the objects of the establishment a n d more important, would be the systematic study of the geological relations to each other of the several different formations represented in the mountain. It was for this purpose that the contoured m a p of the South Mountain was r e c o m m e n d e d a n d c o m m e n c e d u n d e r the direction of the former Assistant of the Southeast District of Pennsylvania. W h y not allow his well-matured plan to r e a c h fruition ?
Mar., I887.]
Book Notices.
233
No proper effort has b e e n m a d e by the chief geologist to harmonize the conflicting views of the arch~ean a n d palmozoic geology of Chester, Delaware a n d Philadelphia, although they are parts of the geological column which are claiming the attention of geologists all over the world. It is a matter of speculation to what extent the " s p e c i a l local surveys in Chester a n d Delaware Counties" c a n conduce to this end. A n appropriation of $90,000 is asked for the next two years. A great state like P e n n s y l v a n i a should h a v e a p e r m a n e n t geological bureau, economically administered, a n d charged with collecting, a r r a n g i n g a n d publishing the valuable information, which is lost in its absence every year. T h e h e a d of such a bureau should be a m a n of large experience a n d industry, without prejudices that influence his work. F. THE STORY OF THE ROCKS. T h e E a r t h ' s A n n u l a r System. By Isaac N. Vail, with an introduction by Capt. R. Kelso Carter, Barnsville, O., Published by the author. 8vo, 375 PP. Appen. a n d Index. It is a trait characteristic of most iconoclastic reform, that no matter what m a y be its subject, its apostles h a v e a strong family resemblance, and argue (they would say reason) in the family dialect. W e will suppose a being to h a v e spent, say, thirty or forty years in the honest e n d e a v o r to fit himself for the u n d e r s t a n d i n g of the intricate a n d unsolved problems of geology. H e has diligently searched out the best authors, a n d the best living teachers, a n d by the aid of both, a n d years of experience in the field, he is b e g i n n i n g to realize how little m a n can know o f . t h e great genetic problems c o n n e c t e d with these studies, a n d to value the contributions to our knowledge m a d e by the master m i n d s devoted to them, though but a small part of the whole truth ; w h e n along comes a genius a n d tells him in the first line of his Preface that " t h e readers of this volume must first divest their minds as far as possible of pre-conceived opinions, however p e r m a n e n t l y time a n d education m a y h a v e i m p l a n t e d t h e m . " W i t h this b e g i n n i n g , one braces oneself to hear a tremendous deliverance, which shall prove the necessity of "a thorough reorganization of the geologic record, as now interpreted." This turns out simply to be that the earth once possessed a ring, or system of rings, of aqueous vapor around its hot nucleus, a n d that the v a p o r was prevented from descending by the velocity of its rotation a n d by the heat of the central mass. Most geologists, on reading this, will ask what it has to do with the "geologic record ?"; a n d wherein consists its novelty ? It has been held to be one of the p r o b a b l e transition states in the earth's genesis, ever si0ce LaPlace (somewhat before Prof. Winchell) e n u n c i a t e d his " s u b l i m e conception," of which it is a corollary. As to the waters r e m a i n i n g suspended in the air for a considerable time after the earth was cool enough to hold them, very few could be found to take a n y other view : least of all that, that the waters descended all at once. A m o n g s t others, Dr. T. Sterry H u n t h a s very elaborately a n d graphically described this very condition of acid rains on the cooling earth, a n d perpetual clouds in the atmosphere, in his, " S o m e Points in Chemical Geology' (i857),
The #'low of Metals. OF M E T A L S
IN THE D R A W I N G
[J. F. I., PROCESS.
ADDENDUM.
IN MR. OBERLIN SMITH'S LECTURE upon the "Flow of Metals," etc., upon page 23 of the JOURNALfor November, I886, equation (5) should read 2 ( / + r ' ) - - 2 e ~--- r - - instead of with the sign of equality after the first 2, as the printer made it to read. To make clearer the derivation of equation (3), it m a y be said that therein the value x has been found for sharp cornered work, w h o s e " c o n t o u r " is, of course, its diameter plus twice its height. In equation (6) the value x is decreased by r - because its contour is that much less, by the amount r __ at each corner, as shown in 2 equation (4). This assumes that there is no radial stretch in arc e, due to the " drawing" action. Practically this is nearly true for corners of small radius, but not for large ones, as explained in the previous paragraph. BOOK
NOTICES.
REPORT OF THE BOARD OF COMMISSIONERS OF THE GEOLOGICAL SURVEY OF PENNSYLVANIA TO THE LEGISLATURE, J a n u a r y I, I887. This small p a m p h l e t of six pages contains two small maps of the state, colored to represent the counties of which geological reports h a v e been published, a n d the counties of which colored geological maps h a v e b e e n published. It" gives a list of the work done in the field a n d by the printing-press during the last two years, a n d specifies fifteen odd jobs throughout the state which r e m a i n to b e done. A m o n g them, is " a detailed mineralogical s u r v e y " of the South Mountain, in Cumberland, York, F r a n k l i n a n d A d a m s Counties, " for whic.,k we h a v e a perfect m a p basis." This m a p basis (doubtless L e h m a n ' s contoured m a p of the South Mountain) will prove a very important addition to the survey's records, but it was not k n o w n before this a n n o u n c e m e n t that it was completed. A " m i n e r a l o g i c a l s u r v e y " is one of those singularly u n h a p p y expressions which, like h u m a n society in travail,' voices a w a n t for which itself c a n n o t find words ;' or, at least, the right ones. However interesting a mineralogical survey, or a search for minerals m i g h t be, a work more in keeping with the objects of the establishment a n d more important, would be the systematic study of the geological relations to each other of the several different formations represented in the mountain. It was for this purpose that the contoured m a p of the South Mountain was r e c o m m e n d e d a n d c o m m e n c e d u n d e r the direction of the former Assistant of the Southeast District of Pennsylvania. W h y not allow his well-matured plan to r e a c h fruition ?
Mar., I887.]
Book Notices.
233
No proper effort has b e e n m a d e by the chief geologist to harmonize the conflicting views of the arch~ean a n d palmozoic geology of Chester, Delaware a n d Philadelphia, although they are parts of the geological column which are claiming the attention of geologists all over the world. It is a matter of speculation to what extent the " s p e c i a l local surveys in Chester a n d Delaware Counties" c a n conduce to this end. A n appropriation of $90,000 is asked for the next two years. A great state like P e n n s y l v a n i a should h a v e a p e r m a n e n t geological bureau, economically administered, a n d charged with collecting, a r r a n g i n g a n d publishing the valuable information, which is lost in its absence every year. T h e h e a d of such a bureau should be a m a n of large experience a n d industry, without prejudices that influence his work. F. THE STORY OF THE ROCKS. T h e E a r t h ' s A n n u l a r System. By Isaac N. Vail, with an introduction by Capt. R. Kelso Carter, Barnsville, O., Published by the author. 8vo, 375 PP. Appen. a n d Index. It is a trait characteristic of most iconoclastic reform, that no matter what m a y be its subject, its apostles h a v e a strong family resemblance, and argue (they would say reason) in the family dialect. W e will suppose a being to h a v e spent, say, thirty or forty years in the honest e n d e a v o r to fit himself for the u n d e r s t a n d i n g of the intricate a n d unsolved problems of geology. H e has diligently searched out the best authors, a n d the best living teachers, a n d by the aid of both, a n d years of experience in the field, he is b e g i n n i n g to realize how little m a n can know o f . t h e great genetic problems c o n n e c t e d with these studies, a n d to value the contributions to our knowledge m a d e by the master m i n d s devoted to them, though but a small part of the whole truth ; w h e n along comes a genius a n d tells him in the first line of his Preface that " t h e readers of this volume must first divest their minds as far as possible of pre-conceived opinions, however p e r m a n e n t l y time a n d education m a y h a v e i m p l a n t e d t h e m . " W i t h this b e g i n n i n g , one braces oneself to hear a tremendous deliverance, which shall prove the necessity of "a thorough reorganization of the geologic record, as now interpreted." This turns out simply to be that the earth once possessed a ring, or system of rings, of aqueous vapor around its hot nucleus, a n d that the v a p o r was prevented from descending by the velocity of its rotation a n d by the heat of the central mass. Most geologists, on reading this, will ask what it has to do with the "geologic record ?"; a n d wherein consists its novelty ? It has been held to be one of the p r o b a b l e transition states in the earth's genesis, ever si0ce LaPlace (somewhat before Prof. Winchell) e n u n c i a t e d his " s u b l i m e conception," of which it is a corollary. As to the waters r e m a i n i n g suspended in the air for a considerable time after the earth was cool enough to hold them, very few could be found to take a n y other view : least of all that, that the waters descended all at once. A m o n g s t others, Dr. T. Sterry H u n t h a s very elaborately a n d graphically described this very condition of acid rains on the cooling earth, a n d perpetual clouds in the atmosphere, in his, " S o m e Points in Chemical Geology' (i857),