“Silly child! He was but obeying my sign. He had been taught that trick already under the name of Mop. The only strange thing is, that he should do it also under the name of Sir Isaac, and much more cheerfully too. However, whether he has been the great Newton or not, a live dog is better than a dead lion. But it is clear that, in acknowledging the name of Sir Isaac, he does not encourage us to take that of Newton; and he is right: for it might be thought unbecoming to apply to an animal, however extraordinary, who by the severity of fortune is compelled to exhibit his talents for a small pecuniary reward, the family name of so great a philosopher. Sir Isaac, after all, is a vague appellation; any dog has a right to be Sir Isaac--Newton may be left conjectural. Let us see if we can add to our arithmetical information. Look at me, Sir Isaac.” Sir Isaac looked and grinned affectionately; and under that title learned a new combination with a facility that might have relieved Sophy’s mind of all superstitious belief that the philosopher was resuscitated in the dog, had she known that in life that great master of calculations the most abstruse could not accurately cast up a simple sum in addition. Nothing brought him to the end of his majestic tether like dot and carry one. Notable type of our human incompleteness, where men might deem our studies had made us most complete! Notable type, too, of that grandest order of all human genius which seems to arrive at results by intuition, which a child might pose by a row of figures on a slate, while it is solving the laws that link the stars to infinity! But _revenons a nos moutons_, what was the astral attraction that incontestably bound the reminiscences of Mop to the cognominal distinction of Sir Isaac? I had prepared a very erudite and subtle treatise upon this query, enlivened by quotations from the ancient Mystics,--such as Iamblicus and Proclus,--as well as by a copious reference to the doctrine of the more modern Spiritualists, from Sir Kenelm Digby and Swedenborg, to Monsieur Cahagnet and Judge Edwards. It was to be called Inquiry into the Law of Affinities, by Philomopsos: when, unluckily for my treatise, I arrived at the knowledge of a fact which, though it did not render the treatise less curious, knocked on the head the theory upon which it was based. The baptismal name of the old soldier, Mop’s first proprietor and earliest preceptor, was Isaac; and his master being called in the homely household by that Christian name, the sound had entered into Mop’s youngest and most endeared associations. His canine affections had done much towards ripening his scholastic education. “Where is Isaac?” “Call Isaac!” “Fetch Isaac his hat,” etc. Stilled was that name when the old soldier died; but when heard again, Mop’s heart was moved, and in missing the old master, he felt more at home with the new. As for the title, “Sir,” it was a mere expletive in his ears. Such was the fact,