FOUNDATION-STONE OF ST. MARK'S AT VENICE.

I recollect having seen the stone in question in the collection of the late Mr. Douce, in whose possession it had been for some years before his communication of it to the Society of Antiquaries. It is quite evident that he was satisfied of its authenticity, and it was most probably an accidental purchase from some dealer in antiquities, who knew nothing about it. I happen to know that it remained in the hands of Sir Henry Ellis at the time of Mr. Douce's death, and your correspondent H. C. R. will most probably find it among the other collections of Mr. Douce now in the museum at Goodrich Cas…