Ibid., Vol. VII., pp. 670, 684. 'Chronicon Casinensis 's of Leo of Marsi, better known, after becoming 1212), a compilation by various monks whose names are unknown; the interest for our present purpose are the Annales Casinenses' (1000 FIG. 3 ATTEMPTED RESTORATION OF VESUVIUS PRIOR TO THE ERUPTION OF 1631. From Mecatti, after an early print. A, Barra; B, Massa Bishop of Ostia, as Leo Ostiensis, one of the most sober and important of Italian historians; the Annales Cavenses' (569-1318), produced by another famous monastery near Salerno; and finally the Chronicon' (1102-1140) 10 of Falco of Benevento, notary, judge and papal chancellor, to whom posterity is indebted for precious information. These contemporary sources contain all that is known of the ninth and tenth Vesuvian eruptions. Details are wanting, but it is said of the former that it happened in January, 1037, and lava flows reached the sea; the duration of the latter (1139) is stated in one account to have been eight, in another, forty days. Critical estimates of the documents above referred to will be found in various works dealing with the sources of medieval history, amongst which it will be sufficient to mention an article by Hirsch on 'Desiderius of Monte Cassino." Our review of the chronology of eruptions in the early middle ages is now completed. 911 There remains to be considered a question that has often been asked, and variously answered: was the form of Somma-Vesuvius essentially the same in antiquity as we know it to-day, or were the ancients acquainted with only a single crateriform summit whose broken wall now partially encircles the newer cone? The only reason for raising the inquiry at all is that neither by direct statement nor by implication do any of the ancient authors allude to Vesuvius as a double-peaked mountain, and the older topographic descriptions can with difficulty be reconciled with the present form of the volcano. It appears indeed passing strange that Strabo, Pliny, Cassius Dio and Procopius should all have remained silent respecting the most salient feature of Vesuvius as viewed from the west, in case its twin peaks presented to their eyes, as they do to ours, almost identical outlines. Yet, accepting their accounts at face value, the only conclusion possible is that the younger cone has been entirely built up during the middle ages, a far shorter interval than is demanded by geologic evidence. A time allowance of barely a thousand years (or at the most fifteen hundred, if we leave Procopius out of the reckoning and admit the correctness of Leone di Ambrogio's figure of a double summit in 1514) for the formation of the central cone is absurdly inadequate, the number of eruptions contributing towards it too few, and their intensity too slight, to have performed the work. This we know from the present slow rate of accumulation, and from the relatively unimportant changes wrought by even paroxysmal eruptions. And it may well be doubted whether the convulsion of 79 A. D. was of more violent character than those of 1631 and 1906, these three exceeding all others in intensity. 10 Muratori, R. I. S., Vol. V., p. 128. 11 Forsch. deutsch. Gesch., Vol. VII., 1867, pp. 1-112. FIG. 4. ATTEMPTED RESTORATION OF THE PARTHENOPIAN VOLCANO AS IT APPEARED IN STRABO'S TIME. After Pellegrino, 1651. (The site of Veseri is conjectural.) The problem of the geologist is to determine the past condition of things from what he is able to find out from the present. Nevertheless, the tendency of popular opinion has been to subordinate geologic to documentary evidence, and the majority of standard works continue to uphold the view that Vesuvius proper was non-existent at the time Herculaneum and Pompeii were overwhelmed. As positive a statement of this view as any is the following, from Professor Phillips' excellent work on 'Vesuvius': Somma, the broken crest of a greater and earlier volcanic crater, has been unmoved in place, unchanged in form and height, through eighteen centuries; a grand and awful fragment left after the poetic struggle of earth and sky,' and full of peculiar records of the combat. Vesuvius, born of Somma, and seated within the encircling grasp of its parent, is a variable heap thrown up from time to time, and again, not seldom, by a greater effort of the same force, tossed away into air. Thus two classes of forms arise in the history of Vesuvius: one may be called the old or Somma form, left after violent and exhaustive efforts of the volcano; the other the new form, in which Vesuvius takes a place unrecorded in ancient history (p. 174). Equally confident is the tone assumed by Professor Judd, in his volume on Volcanoes,' in the International Science Series: Nothing is more certain than the fact that the Vesuvius upon which the ancient Romans and the Greek settlers of southern Italy looked, was a mountain differing entirely in its form and appearance from that with which we are familiar. The Vesuvius known to the ancients was a great truncated cone, having a diameter at its base of eight or nine miles, and a height of about 4,000 feet. The summit of this mountain was formed by a circular depressed plain, nearly three miles in diameter, within which the gladiator Spartacus, with his followers, were besieged by a Roman army (p. 83). The above description is reinforced by a figure of a truncate colossus, supposed to represent Vesuvius in the time of Strabo, a graphic portrayal that has been popular ever since the first attempt in this direction was essayed by Camillo Peregrino,12 in 1651. Strange as it may seem, some writers have been misled into supposing that such was the actual form presented by the mountain in the middle of the seventeenth century. As a matter of fact, all these fanciful restorations of the Somma form of crater, however cleverly they may interpret geological evidence, and to that extent suggest remote prehistoric conditions, can not be considered as having any real historical foundation. For we have no right to interpret literary documents in a manner wholly discordant with what is known of the structure and behavior of the mountain itself, but rather should first seek to establish their credibility by scrutinizing them in the light of ascertained facts. If it has been easy to misconstrue Braccini's account of the crater in the first quarter of the seventeenth century, should we not be wary of accepting the usual rendering of ancient authors? And who is so bold. as to claim that the huge truncate cone of which Strabo is commonly understood to speak finds any visible support in Pompeiian wall frescoes, of which several representing Vesuvius in a more or less idealized fashion have been discovered? Impressionistic as all of these paintings are, it is not difficult to perceive that the local scene which caught the artist's fancy was after all not very different from that which still meets our gaze from within or hard by the disinterred city.13 We may affirm, then, this conclusion: there is no good reason to suppose that Vesuvius appeared materially different in the yesterday of one or two thousand years ago than it does to-day. The summit of the younger cone, still partially encircled by the ancient Somma rim, has been undergoing comparatively slight modification throughout probably the whole course of human history. And we must perforce believe it to have been existent even before the race of man had appeared on the face of the earth, and had begun to acquire dominion over it. 12 Discorsi della Campania Felice,' p. 309. (Naples, 1651.) 13 For a recent and interesting discussion of this whole matter, and also of the events of the Plinian eruption, one may consult the following: Enrico Cocchia, La forma del Vesuvio,' an essay reprinted in Volume III. of his 'Saggi Filologici' (Naples, 1902); and S. Herrlich, Die antike Ueberlieferung über den Vesuv-Ausbruch im Jahre 79.' Beitr. zur alten Gesch., Vol. IV. (1904), pp. 209-226. THE PROGRESS OF SCIENCE. THE NEW ENGINEERING BUILD- PENNSYLVANIA cord with the later university halls. There are three stories, the total floor area being 128,000 square feet. The THE new engineering building of the heating is by direct steam; the ventiUniversity of Pennsylvania was dedi- lation by electrically-driven fans, and cated on October 19, in the presence the lighting by electricity. The steam of delegates from over one hundred for the engines is supplied from the scientific institutions and societies and central station of the university, and, representatives of six leading foreign after being used by the engines, is sent nations. The building was open for in- into the heating system of the building. spection in the morning, and after There are two principal entrances leadluncheon had been served in the build- ing to the main hallway, which extends ing the formal ceremonies took place. east and west the entire length of the Provost Harrison accepted the building building to staircases at both extremion behalf of the trustees, thanking ties. The basement contains locker especially Professors Spangler and rooms, lavatories, machinery for heatMarburg, the heads of the departments ing and ventilating, storage battery of mechanical, electrical and civil engi- rooms, laboratories for geodetic and neering that occupy the building, the hydraulic work, and for the testing of architects, Messrs. Cope and Steward- the materials of construction. On the son, the workmen and the numerous first floor, adjacent to the main endonors who had made the building pos- trance, are the offices of the heads of sible. The degree of doctor of science departments, the eastern part of the was conferred on a number of eminent building being devoted entirely to the engineers, and the principal addresses civil engineering department, and the were made by Mr. Frederick W. Tay- western part to the mechanical engilor, the president of the American So- neering department. Accommodation is ciety of Mechanical Engineers, and Dr. also provided for physical and hyAlexander C. Humphreys, president of draulic testing, instrument testing and the Stevens Institute of Technology. for special work in mechanical and The building, a view of which and a electrical engineering. Rooms are likegeneral plan of the first floor are wise set aside for dynamos and elecshown in the accompanying illustra- tric motors, steam and gas engines, tions, is the largest of the seventy refrigerating apparatus, hydraulic mobuildings now occupied by the Univer- tors, boiler testing, pattern-making, sity of Pennsylvania, having a front- wood and iron working, foundry and age of 300 feet and a depth of 210 feet. | machine shops, etc. On the second The cost, including equipment, was floor is a reference library and reading almost one million dollars. It is of room, a students' assembly room, rooms fire-proof construction, and the equip for the use of instructors and for lecment is of the most modern and ap-tures and recitations. The rear portion proved type. The exterior is of dark of this floor is devoted almost wholly brick, with limestone trimmings, and to drawing rooms. A room for the use the general architectural treatment is of the engineering societies, a general in the English-Georgian school, in ac- supply store, and the library stack oc |