200 Reply to Mr. Dc Luc. 



be smaller. It consists only of six tiers or ranges of stone; the 

 pyramid itself being 150 feet in height. The ranges of steps are 

 twenty-five feet high and eleven feet wide. The rest of these 

 structures are so fully and accuraiely descril)ed by Pococke, that 

 little will be added here to his description of them. 1 here is 

 one built also with steps, which he believed to be as large as the 

 princi]nil pyramid at Djiza. The works at J^acciira, indepeur 

 dently of the different forms which characteiizc them, do all ap- 

 pear to be older than those of Djiza ; the buildings being mor© 

 decayed, and the stones crumbling, as if decomposed by longer 

 exposure to the action of the atmosphere. Four miles to the 

 south of Saccara stands a pyramid built of unburned bricks. 

 This is in a very mouldering state. The bricks contain shells, 

 gravel, and chopped straw ; they are of the same nature as the 

 unburned bricks in modern use in Egypt, Pococke concluded, 

 from its present appearance, that it was built with five grada- 

 tions only. It is of the same height as the other graduated py-r 

 ramid of six degrees*. 



[To be continued.] 



XXXVII. Ohservatjons on a Paper by G. A. De Luc, Esq. 

 conlaining some Remarks on Mr. Donov'an's Rejections 

 concerning the Inadequacy of eleclrical Hypotheses. By 

 M. Donovan, Esq. 



To Mr. Tilloch. 



Sir, — In your last ere contained some Observations on my 

 ?' Reflections on the Inadequacy of the principal Hypotheses to 

 explain the Plisnomena of Electricity," by Mr. De Luc. Any 

 thing from the pen of that venerable and distinguished philoso- 

 ])her is deserving of the highest consideration: you will therefore 

 allow a place to a few observations in reply. 



It may in the first place be necessary to apprise Mr. De Luc 

 of a misconception into which he has been led, no doubt, l)y 

 5ome defect in the statement of my objections to the Frankliuiun 

 hypothesis. 



The hypothesis of electric excitation, in which it is sup))osed 

 that, during the attrition of glass, the pores by opening receive 

 electricity, and expel it when they close, is attributed by Mr. 

 De Luc to me. To this, however, I have no title ; it is a state- 



* The author afterwards examined (lie catacombs here and at Alexan- 

 dria; and he has furnibhed abundant evidence, from tlie position of the 

 Sorui found in the h tter, and from the height of the space in whicli tlie 

 uiunitnies wore deposited, that in these cemeteries they were invariably 

 pUpetj iu ^ horizontal position— not upright as maintained by some audiors. 



ment 



