HISTORY OF ASTRONOMY. l3

greater variety of particularities amongft thofethings which have a gross refemblance ; and hav-ing made new divisions of them, according tothofe newly-obferved particularities, we are then,no longer to be fatished with being able to referan objedl to a remote genus, or very general clr.fsof things, to many of which it has but a looseand imperfedl relemblance. A person, indeed,unacquainted with botany may expect to satisfyyour curiosity, by telling you, that such a vege-table is a weed, or, perhaps in ftill more gene-ral terms, that it is a plant. But a botanist willneither give nor accept of such an answer. Hehas broke and divided that great class of objedlsinto a number of inferior assortments, accordingto thofe varieties which his experience has disco-vered among them; and he wants to refer eachindividual plant to some tribe of vegetables, withall of which it may have a more exadt refemblance,than with many things comprehended underthe extensive genus of plants. A child imaginesthat it gives a fatisfadtory answer when it tells you,that an objedl whole name it knows not is a thing,and fancies that it informs you of something,when it thus ascertains to which of the two mossobvious and comprehensive classes of objedls aparticular impreilion ought to be referred ; to theclass of realities or solid fubftances which it callsthings , or to that of appearances which it callsnothings.

Whatever, in short, occurs to us we are fondof referring to some species or class of things,