I am not so vain as to think that I have here completely finished this great undertaking, with all the advantages of which such a design capable. Nor on the other hand, am I dissident of this Essay, as not to believe it sufficient for the business to which it pretends, namely the distinct expression of all things and notions that fall under discourse.

I am sensible of sundry defects in the severall parts of this Book: And therefore would make my humble motion to your Lordship and this Society, that you would by your Order appoint some of our number, thoroughly to examine & consider the whole, and to offer their thoughts concerning what they judge fit to be amended in it. Particularly in those Tables that concerne the species of Natural bodies; which, if they were (so far as they are yet known an discovered) distinctly reduced and described, This would very much promote and facilitate the knowledg of Nature, which is one great end of your Institution. And besides, the ranging of these things into such an order as the Society shall approve, would afford a very good method for your Repository, both for the disposal of what you have already, and the supplying of what you want, towards the compleating of that Collection, so generously begun of late, by the bounty of M^r Daniel Collwal, a worthy Member of this Society. And by this means, I should not doubt, but that in a very short space, you would have the most usefull Repository in the World.

It is no easie undertaking to Enumerate all such matters as are to be provided for in such a design; But the business of Defining, being amongst all others the most nice and difficult, must needs render it a very hard task for any one to attempt the doing of this, for all kinde of