20th.  Up; and to the Office, and my wife abroad with Mary Batelier, with our own coach, but borrowed Sir J Minnes’s coachman, that so our own might stay at home, to attend at dinner; our family being mightily disordered by our little boy’s falling sick the last night; and we fear it will prove the small-pox.  At noon comes my guest, Mr. Hugh May, and with him Sir Henry Capell, my old Lord Capel’s son, and Mr. Parker; and I had a pretty dinner for them; and both before and after dinner had excellent discourse; and shewed them my closet and my Office, and the method of it to their great content; and more extraordinary, manly discourse and opportunity of shewing myself, and learning from others, I have not, in ordinary discourse, had in my life, they being all persons of worth, but especially Sir H. Capell, whose being a Parliament-man, and hearing my discourse in the Parliament-house, hath, as May tells me, given him along desire to know and discourse with me.  In the afternoon we walked to the Old Artillery-Ground’ near the Spitalfields, where I never was before, but now, by Captain Deane’s invitation, did go to see his new gun tryed, this being the place where the Officers of the Ordnance do try all their great guns; and when we come, did find that the trial had been made; and they going away with extraordinary report of the proof of his gun, which, from the shortness and bigness, they do call Punchinello.  But I desired Colonel Legg to stay and give us a sight of her performance, which he did, and there, in short, against a gun more than as long and as heavy again, and charged with as much powder again, she carried the same bullet as strong to the mark, and nearer and above the mark at a point blank than theirs, and is more easily managed, and recoyles no more than that, which is a thing so extraordinary as to be admired for the happiness of his invention, and to the great regret of the old Gunners and Officers of the Ordnance that were there, only Colonel Legg did do her much right in his report of her.  And so, having seen this great and first experiment, we all parted, I seeing my guests into a hackney coach, and myself, with Captain Deane, taking a hackney coach, did go out towards Bow, and went as far as Stratford, and all the way talking of this invention, and he offering me a third of the profit of the invention; which, for aught I know, or do at present think, may prove matter considerable to us:  for either the King will give him a reward for it, if he keeps it to himself, or he will give us a patent to make our profit of it:  and no doubt but it will be of profit to merchantmen and others, to have guns of the same force at half the charge.  This was our talk:  and then to talk of other things, of the Navy in general:  and, among other things, he did tell me that he do hear how the Duke of Buckingham hath a spite at me, which I knew before, but value it not:  and he tells me that Sir T. Allen is not my friend; but for all this I am not much troubled, for I know myself