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ON THE GLASS OF POMPEI. 



M. G. Bontemps, at one of the late meetings of the Academie des 

 Sciences, read a very interesting paper on this subject. The following are 

 the most salient points of M. Bontemp's communication : — " The use of 

 glass for window-glazing, an invention so useful to the Northern nations, 

 does not seem to claim a high antiquity. Its use among the ancient Greeks 

 and Romans is negatived by the silence of the Greek and Latin writers. 

 The wonderful skill displayed in glass manufacture many centuries before 

 the Christian era, would appear to imply that it was simply a question of 

 climate that glass for window purposes was not made. Philo, the Jew, in 

 the first century of the Christian era, while describing his embassy to the 

 Emperor Caligula, alludes to the employment of window-glass ; Seneca, 

 however, says that it was in his own time that this invention came into use. 

 These assertions have given rise to numberless contradictions in learned 

 commentators ; but the discoveries at Herculanum and Pompei have 

 removed all uncertainty from the question. Mazois, the celebrated archi- 

 tect, in his work ' Les Ruines de Pompei,' (Paris, 1814-1835), in his chapter on 

 the Public Baths (T. II., p. 77), thus writes : — ' K the question of the 

 employment of window-glass by the ancients were still a matter of doubt, 

 We should find in this hall a testimony capable of solving it. Time has 

 still preserved there a bronze window-frame, which shows not only the size 

 and the glass employed, but also the manner of arranging it. The panes of 

 glass were inserted in an incision in the bronze, and kept in their place by 

 small turning buttons which pressed upon the glass ; the size of the panes 

 was about 20 inches broad by 28 inches long, and the thickness more than 

 two lines (5 to 6 millimetres).' " 



The certainty that glass was employed at a period anterior to the year 

 79 of our era, the date of the eruption of Vesuvius, in which Herculanum 

 and Pompei perished being confirmed, it becomes an interesting question 

 to know how these panes of glass were manufactured, which, as we have 

 seen, were of considerable dimensions ; whether they were blown in cylin- 

 ders or in sheets, or whether they were run out like our looking-glass. M. 

 Bontemps asserts that a mere inspection of the fragments is sufficient to 

 determine the method. He says : — " These panes of glass which, according 

 to their size, could not weigh less than five kilogrammes, had the\ been 

 blown, could not have been the product of a single piece ; the joinings then 

 should be observable on the different cuttings. Were these panes the 

 result of the blowing of a cylinder then opened and rolled, the bubbles of 

 the glass should be lengthened and parallel with regard to the axis of the 

 cylinder ; they should be concentric were the panes the result of a globe 

 afterwards flattened out ; were they run out, the bubbles could not assume 

 any uniform direction, and must generally be round and flat." By the 

 kindness of the Minister of Foreign Affairs, the superintendent of the 

 Naples Museum, Prince de San Georgio was induced to send some fragments 

 of the glass found at Pompei to be examined by M. Bontemps. He says : — 



