And the Origins of Modern Meteorite Research URSULAB
Total Page：16
File Type：pdf, Size：1020Kb
Meteor;t;cs & Planetary Science 3 1,545-588 (1996) a Meteoritical Society, 1996 Pnnted in USA. Invited Review Ernst Florens Friedrich Chladni (1756-1827) and the origins of modern meteorite research URSULAB. MARVIN Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02 138, USA Author's e-mail address: [email protected] (Received 1996 April 16; accepted in revised form 1996 July 3) ~ ~ Abstract-In 1794, Ernst F. F. Chladni published a 63-page book Uber den Ursprung der von Pallas gefun- denen und anderer ihr anlicher Eisenmassen und uber einige damit in Verbindung stehende Naturer- scheinungen in which he proposed that meteor-stones and iron masses enter the atmosphere from cosmic space and form fireballs as they plunge to Earth. These ideas violated two strongly held contemporary beliefs: (1) fragments of rock and metal do not fall from the sky, and (2) no small bodies exist in space beyond the Moon. From the beginning, Chladni was severely criticised for basing his hypotheses on his- torical eyewitness reports of falls which others regarded as folk tales and for taking gross liberties with the laws of physics. Eight years later, the study of fallen stones and irons was established as a valid field of investigation. Today, some scholars credit Chladni with founding meteoritics as a science; others regard his contributions as scarcely worthy of mention. Writings by his contemporaries suggest that Chladni's book alone would not have led to changes of prevailing theories; thus, he narrowly escaped the fate of those scientists who propose valid hypotheses prematurely. However between 1794 and 1798, four falls of stones were witnessed and widely publicized. There followed a series of epoch-making analyses of fallen stones and "native irons" by the chemist Edward C. Howard and the mineralogist Jacques-Louis de Bournon. They showed that all the stones were much alike in texture and composition but significantly different from the Earth's known crustal rocks. Of primary importance was Howard's discovery of nickel in the irons and the metal grains of the stones. This linked the two as belonging to the same natural phenomenon. The chemical results, published in 1802 February, persuaded leading scientists in England, France, and Germany that bodies fall from the sky. Within a few months, chemists in France reported similar results and a new field of study was inaugurated internationally-although opposition lingered on until 1803 April, when nearly 3,000 stones fell at L'Aigle in Normandy and transformed the last skeptics into believers. Chladni immediately received full credit for his hypothesis of falls, but decades passed before his linking of falling bodies with fireballs received general acceptance. His hypothesis of their origin met with strong resistance from those who argued that stones formed within the Earth's atmosphere or were ejected by lunar volcanoes. After 1860, when both of these hypotheses were abandoned, there followed a century of debate between pro- ponents of an interstellar vs. a planetary origin. Not until the 1950s did conclusive evidence of their elliptical orbits establish meteorite parent bodies as members of the solar system. Thus, nearly 200 years passed before the questions of origin that Chladni raised finally were resolved. TABLE OF CONTENTS Portugal, 1796 ............................................................................... 564 Mulletiwu, 1795; Bielaya Tserkov, 1796; Salles, 1798 ................ 564 Ironmasses, 1794 April ................... Meteoritics in the Late-Eightee Late-Twentieth Centuries.. ............ Chladni's Hypotheses.................................. Fireballs ......................................................................................... 549 Stones and Irons from the Sky ...................................................... 551 551 Analyses By Edward Howard and Atmospheric Origin .................................................... 552 Jacques-Louis de Bournon: 1802 .......................................... 567 Chladni's Compilation of Witnessed Falls ........................................... 552 A Second Small Planet: Between Mars and Jupiter ..................... 568 EichstKdt, Bavaria, 1785 ............................................................... 552 Lunar Volcanic Origin: Laplace's Hypothesis? ........... Tabor, Bohemia, 1753 .............. The Debates Intensify.................. .................569 Hraschina (Agram), Croatia, 17 New Falls: Fresh Evidence ................................. Pre-eighteenthcentury Falls ......................................................... 554 The Fall at Salles, France, 1789: A Belated Additonal Eighteenth-Century Falls ......... 554 De Drke, 1803: The First Meteorite Classifi Native Irons .................................................... 556 The Fall at L'Aigle, France, 1803 ................................................. 571 The Pall .................................................... 556 Josdf Izam: Lithologie AfmosphPrique, 1803 .............. 572 The Mesh De Fierro, Camp0 del Cielo, Argentina ..................... 557 Metallography Of Irons: Thomson, 1804; The Aken (Aachen) Mass ....................... Von WidmanstKtten, 1808 ...................................................... 574 German Responses to Chladni, 1794 ............ Two More Small Planets Discovered Two Witnessed Falls, 1794-1795 ................. between Mars and Jupiter ................................. Siena, Italy, 1794 .......................................................................... 558 Pierre M. S. Bigot de Wold Cottage, England, 1795 December of Meteoritics, 1812 ................................. 577 Edward King On Fallen Stones, 1796 .................................................. 561 Meteorite Origins: From Responses to King's Book ............................................................. 562 Origins Within the Earth-Moon System ........................................ 577 News Relating to Meteorites Crisscrosses Europe Asteroidal versus Interstellar Origin, circa 1854-1959 ................579 Stones Kept Falling ............................................... Meteorites from Asteroids and Other Planets 581 545 546 U. B. Marvin FIG. 1. Emst Florenz Friedrich Chladni. (Reproduced by courtesy of Deutschen Staatsbibliothek, Berlin.) Chladni and the origins of modern meteorite research 547 premature Ideas in Meteoritics ................................................ 583 right so early about his principal hypotheses that today many mete- TWO Treatises by Franz oriticists share the view expressed by Wolfgang Czegka (1993:376): The "Firsts" of William "Chladni founded meteoritics as a science by this paper." Ironmasses by Ernst Ch Catastrophic Impacts ..... Others, more cautious, credit Chladni with laying the ground- Conclusions: The Founding work for meteoritics' but question whether any one person founds a Chladni's Views on the New Science: 1809.................................. 584 new science. A warning against such claims was issued in 1982 by IRONMASSES, 1794 APRIL Reijer Hooykaas (1906-1 994), the distinguished historian of science in The Netherlands. He argued that too many authors develop a ten- At Eastertime in 1794 April, a book by Ernst F. F. Chladni (Fig. dency to hero-worship and then exaggerate the intellectual virtues of 1) was published simultaneously in two cities: Leipzig, to reach their heroes and overlook the merits of earlier and contemporary physicists and astronomers in Germany, and Riga, to reach a Ger- scholars. Hooykaas (198 1-1 982:22) wrote, man-reading public in northern Europe. The book, On the Origin of Like most saints, those of the Church Scientific seem to perform the Mass of Iron found by Pallas and of other similar Ironmasses, miracles and, in some cases, they give birth to a new science, and on a Few Natural Phenomena Connected Therewith, commonly which before they appeared on the scene, existed at best in an em- is called Ironmasses (Fig. 2). By featuring in his title a large mass bryonic state. of iron described by Pallas, Chladni sought to capture some of the As one example, Hooykaas cited the following statement by R. widespread interest aroused by the book of travels in Siberia pub- Marcard in his 1938 history of chemistry and alchemy: lished in 1776 by the celebrated German natural historian Peter Chemistry, like Minerva of old, sprang fully grown from the head Simon Pallas (1741-181 1). The Few Natural Phenomena of the of a most eminent French savant named Lavoisier. title were fireballs and fallen stones and irons. We know better about chemistry. The roots of modern chem- From boyhood, Chladni, born in Wittenberg in 1756 November istry were established well before 1789 when Antoine-Laurent de 30, held strong interests in mathematics, physics, music, and natural Lavoisier (1 743-1 794) issued his Trait6 e'le'mentaire de Chimie in history. However, at the insistence of his father, a professor and Dean which he enunciated the principle of conservation of mass and pro- of Jurisprudence at the University in Wittenberg, he studied law and vided a wealth of new insights on chemical reactions and cornbina- philosophy at Leipzig and Wittenberg. In 1782, he earned his doc- tions. Earlier contributions of importance included the works of torate of philosophy and law at Leipzig. Soon afterward his father Torbern Bergman (1735-1784) in Sweden who had described the died, leaving him no fortune other than the freedom to pursue his apparatus and techniques for