28 Dr. Smitn’s Introductory Difcourfe. 
Tournefort’s having maintained the vegetation of ftones, and 
Lifter’s having pofitively afferted that all extraneous foffils, as petri- 
fied fhells, &c. are only lufus natura, and never were the real fhells 
they reprefent. Afterwards Mineralogy was cultivated with a little 
more care, but {till on wrong principles, the external figure of 
foffils being principally attended to, and not their component 
parts; nor was it till very lately that the {cience was eftablifhed on 
its true foundation, that of chemical analyfis. 
For about fifteen years after the beginning of the prefent century 
nothing very confiderable was printed in botany. But the year 
1718 is remarkable for the publication of Ruppius's excellent 
Flora Jenenfis, and the following for the appearance of Scheuch- 
zers inimitable Agroftographia and Dillenius’s Flora Giffenfis. 
. Ruppius being cut off early in life, difappointed the hopes which 
were formed of him. Dillenius is one of the moft illuítrious names 
in botany; not fo much indeed for fyftematic or phyfiological 
merit, as for accuracy of obfervation and judicious criticifm. 
‘About this time alfo flourifhed Pontedera at Padua, who although 
a great Tournefortian, and ftrangely prejudiced againft the fexes of 
plants, was a fcientific botanift, and is very liberally praifed by 
Linnæus, againft whom he is faid neverthelefs to have written 
fomething, which was never publifhed. 
The removal of Dillenius to England, who publifhed here his 
excellent edition of Ray’s Synopfis Stirpium Britannicarum in 1724; 
the affiftance and encouragement given to the fcience by thofe two _ 
diftinguifhed brothers William and James Sherard, as well as by 
Sir Hans Sloane, feemed to promife the eftablifhment of the botanic 
fceptre in this country ; efpecially as the infufficiency of Tourne- 
fort’s fyftem became every day more obvious, and Boerhaave was 
too much occupied by medicine, to devote any confiderable fhare 
of his powers to any other purfuit. The phyfick garden at Chel- 
4 fea 
