A VEGETABLE TIMEPIECE. 19 



entirely in a dormant state. From these facts he 

 formed his theory of the sleep of plants, and 

 proved that it occurred at regular periods, like 

 that of animals. This discovery gave him the idea 

 of forming a sort of vegetable timepiece, in which 

 the hours of the day were marked by the opening 

 and closing of certain flowers ; and in the same 

 manner he formed a rural calendar for the regula- 

 tion of the labours of husbandry. The tables in this 

 " Calendariurn Florae," as it was designated, were 

 formed from observations made on the common 

 plants of Sweden, in the garden at Upsala, in 1755. 

 Mrs Hemans' pretty lines on this subject may pro- 

 bably recur to the mind of the reader : 



" 'Twas a lovely thought to mark the hours, 

 As they floated in light away, 

 By the opening and the folding flowers 

 That laugh in the summer's day. 

 Yet is not life, in its real flight, 

 Mark'd thus even thus on earth, 

 By the closing of one hope's delight 

 And another's gentle birth ? 

 Oh ! let us live so that flower by flower, 

 Shutting in turn, may leave 

 A lingerer still for the sunset hour 

 A charm for the shaded eve." 



