Chapter I: AS to the First, some most famous AUTHORS have written their Minds

freely and copiously upon it, and have given certain pertinent _Instructions_, touching the _Time_, and _Manner_, as well as _Conduct_ of the _Parties_ concern’d, both before and after the ACT: Particularly _Avicenna_[37] (no _Proletarian Writer_, but a most Illustrious and most Learned _Prince_) has insisted at large upon every Case belonging to this Head, together with the _Way_ and _Manner_, as well as the proper _Time_ of begetting either SEX; _“Ubi, inquit, menses defluxerint, sitq; abstersus Uterus, quod quinto ferè die usu venit, aut septimo; Si Vir Mulieri congrediatur, à primo quàm est purgata die ad quintum, MAREM produci: à quinto verò ad octavum, FÆMELLAM: rursus ab octavo ad duodecimum denuo, MASCULUM, &c.”_

WHICH excellent Opinion is fully proved by _Levinus Lemnius_ (another great _Master_ of NATURE): According to whose authentick Judgment also, there are likewise many things[38] of an _occult specifick Quality_, and _secret Effect_, for answering the same ENDS, as well as _Fecundity_ itself: which both common _Reason_ and daily _Experience_ confirm for TRUTH.

BUT because I lie under the Disadvantage (at present) of writing in our _vernacular Tongue_, it may be proper to pass by, what (otherways) might be plentifully said on this _Head_: However I shall observe, that the _Generality_ of RULES are most commonly calculated for _Persons_ of a discording Constitution of natural _Temperaments_ and _Faculties_; which _Difference of Constitution_ brings often false and ungrounded _Reproaches_ upon the Reputation of fruitful WOMEN. From whence it is justly to be remarked, that, tho’ few or no _Children_ are got meerly by ART; yet if a little _Dexterity_ or ingenious _Subtilty_ was used with some WOMEN, there would not (perhaps) _One_ in _Three_ of those, who are rashly accounted so, be found _BARREN_.