242' 



Mt-dicines, 



their 



Operation 



•explained. 



^he Jrt of F AKV. IE ^^ 



Account of the Operation of Diuretick Medicines. 



And firft. ■ . , , , 



Under the Term Diuretick may be comprehended 

 all thofe Medicines whofe moft remarkable Proper- 

 ties appear in their Increafmg the Difcharge by 

 Urine, or which are fuppoied to have any Power in 

 removing Obil:ruaions of the urinary Glands, or 

 PaiTages from what Caufe foever, whether Hw 

 Tnourl Gravel or other offending Matter. And m 

 this View, Diureticks come under thefe following 

 Kinds ; to wit, they are either fuch as foften and 

 lubricate the Fibres compofmg the unn ny Glands 

 and Canals, by which they yield and relax into 

 their due Dimenfions and Capacities ; of which 

 Kind are all Emollients already explained r Or they 

 are fuch as by their attenu?.ting and deterfive Pro- 

 perties, rarefy and thin vifcous or ilimy Iiamours, 

 and adhere to, and carry them along in the Paflages : 

 Or again, they muft be fuch as have a Power of lo 

 alterin? the Cra£s orMixture of the Humours, a^s 

 to fit thofe to pafs, which could not get through 

 before ; and of this Kind is the Soaf of T^/Z^r men- 

 tioned, as well as all the Tribe of Lixi^iah ^xi^ 

 fixed Salts. But, without venturing too far, trom 

 the Compafs here allotted, into theN^'ture of Secre- 

 tion, it may be proper to take Notice, that the 

 thinner Separations increafe in Proportion to the 

 Blood's Velocity : For the Swiftnefs of its Motion 

 not only keeps the Parts more divided, but alio 

 brings them oftener to the fecrctory Orifice; and 

 this every where is that which takes off the tmn- 

 neft of the Blood at that Part. Some of the vifcid 

 and thicker Secretions requiring, for tne ftme Kea- 

 fon a vaft Check of the Blood's Motion before they 

 can be performed; that is, before the Blood has 

 obtained fuch a Confillence by the Slowr^eis of its 

 Motion, that what is to be feparated is tne thicket 

 at that Part. If therefore frcm any Cauie the 

 Blood does not move with its due Velocity, its 

 F^rts will attraa one anoUier, and make the who.e 



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