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Scientific Intelligence. 



7. On the successive Changes of the Temple of Serapis; by Sir Charles 

 Lyell, F.R.S., (Proc. Roy. Inst, of Great Britain, March 7, 1856.)— The 

 Temple of Serapis, near Naples, is, perhaps, of all the structures raised 

 by the hands of man, the one which affords most instruction to a geolo- 

 gist. It has not only undergone a wonderful succession of changes in 

 past time, but is still undergoing changes of condition, so that it is ever 

 a matter of fresh interest to learn what may be the present state of the 

 % temple, and to speculate on what next may happen to it. This edifice 

 was exhumed in 1V50, from a mixed deposit, extending for miles along 

 the eastern shores of the bay of Baise, and consisting partly of strata 

 containing marine shells, with fragments of bricks, pottery, and sculpture, 

 and partly of volcanic matter of subaerial origin. Various theories were 

 proposed in the last century to explain the lithodomous perforations, 

 and attached serpulse, observed on the middle zone of the three erect 

 marble columns now standing ; some writers, and the celebrated Goethe 

 among the rest, suggesting that a lagoon had once existed in the atrium, 

 filled, during a temporary incursion of the sea, with salt water, and that 

 marine mollusca and annelids flourished for years in that lagoon, at a 

 height of 12 feet or more above the sea level. This hypothesis was ad- 

 vanced at a time when almost any amount of fluctuation in the level of 

 the sea was thought more probable than the slightest alteration in the 

 level of the solid land. In 1807, the architect Niccolini observed that 

 the pavement of the temple was dry, except when a violent south wind 

 was blowing; whereas, on revisiting the temple 15 years later, he found 

 the pavement covered by salt water twice every day at high tide. This 

 induced him to make a series of measurements from year to year, first 

 from 1822 to 1838, and afterwards from 1838 to 1845 ; from which he 

 inferred that the sea was gaining annually upon the floor of the temple, 

 at the rate of about one-third of an inch during the first period, and 

 about three-fourths of an inch during the second. Mr. Smith, of Jordan- 

 hill, when he visited the temple in 1819, had remarked that the pave- 

 ment was then dry, but that certain channels cut in it for draining off the 

 waters of a hot spring, were filled with sea water. On his return, in 

 1845, he found the high-water mark to be 28 inches above the pavement, 

 which, allowing a slight deduction on account of the tide, exhibited an 

 average rise of about an inch annually. As these measurements are in 

 accordance with others, made by Mr. Babbage in 1828, and by Professor 

 James Forbes, in 1826 and 1843, Mr. Smith believes his own conclusion 

 to be nearest the truth, and attributes the difference between his average 

 and that obtained by Niccolini (especially in the first set of measurements 

 by the latter observer), to the rejection by the Italian architect, of all the 

 highest water-marks of each year, causing his mean to be below the true 

 mean level of the sea. In 1852, Signor Arcangelo Scacchi, at the re- 

 quest of Sir Charles Lyell, visited the temple, and compared the depth of 

 water on the pavement with its level as previously ascertained by him- 

 self in 1839, and found, after making allowance for the tide at the two 

 periods, that the water had gained only 4-J inches in thirteen years, and 

 was not so deep as when measured by MM. Niccolini and Smith, in 1 845 ; 

 from which he inferred, that after 1845, the downward movement of the 

 land had ceased, and before 1852, had been converted into an upward 



