VISIT TO ENGLAND 
165 
was inducted into a club, where Dr. J. F. Gronovius, 
Dr. van Swieten, himself, Isaac Lawson, Lieber- 
kuhn, a big and stout Prussian, who had matchless 
microscopes, J. Kramer, a fast and careless German, a 
student in all the faculties (with incomparable genius 
for remembering everything which he had heard or 
read), with J. Bartsch, were members. When they 
were gathered together, it was the duty of the host to 
demonstrate something in his province, as Gronovius in 
botany, van Swieten in practical medicine, Linnaeus 
in natural history, Lawson in history and antiquities, 
Lieberkuhn in microscopical subjects, Kramer in 
chemistry, and Bartsch in physics. That Linnaeus 
was the active spirit in this society, appears from a 
letter of Gronovius to his friend Dr. R. Richardson of 
North Bierley, in Yorkshire, in which he states: “ Last 
winter we had a most excellent club or union which 
met each Saturday, with Linnaeus as President. Some¬ 
times we examined minerals, other days flowers, insects 
or fishes. We made such progress that with the help 
of his tables [Systema Naturae] we could refer each 
fish, plant or mineral to its genus, and subsequently to 
its species, although none of us had seen it before. I 
consider these tables to be of the highest value, and 
everybody ought to have them, hanging up in his study, 
like maps. Boerhaave values this work highly, and 
they are his daily recreation.” 
Other work of Linnaeus in Leyden consisted chiefly 
in drawing up and printing his “ Classes plantarum ” 
and his deceased friend Artedi’s “ Ichthyologia,” both 
of which came out in 1738. He also helped Gronovius 
with his “ Flora virginica ” in which Linnaeus’s 
principles were embodied. According to his custom 
he was very busy here, but not to that degree as in his 
last days at Hartecamp, with soul and body in ceaseless 
toil. From this it resulted that at Leyden, though 
he no longer lived as splendidly as a king, he became 
stouter and lively, though he still laboured abundantly. 
His economic condition was excellent, as he lived well 
