in different Branches of Science. 63 



La Billardiere, who went round the world with d'En- 

 trecafteaux, brought back with him a valuable collection in 

 every part of natural hiftory. His herbal is moll beautiful ; 

 and though nearly one fourth of it has been loft, he has ftill 

 about three thoufand plants, of which from twelve to fifteen 

 hundred are new. 



He carried with him from the Friendly Ifles twenty- two 

 bread-fruit-trees, twelve of which were left at the Ifle de 

 France. Of the eight brought to France, five died •, two 

 have been fent to Cayenne ; and the other was brought to 

 Paris, where it is now in the Javelin des Plantes. 



La Billardiere brought with him alfo about three hun- 

 dred birds, a third of which almoft are unknown. His 

 collection of infects has been much damaged ; but he has 

 ftill a great many in fufheient prefervation to be defcribed. 

 Riche, who went on the fame expedition, brought with 

 him a variety of obje&s, and particularly birds. He died 

 not long ago. 



Michau has returned from South America, and brought 

 with him a great number of plants in excellent prefervation. 

 He will no doubt foon publifh an account of them, as well 

 as of thofe which he brought from Perfia. 



Coulomb having ordered fome poplars to be cut down in 

 the fpring time, obferved, that when the axe approached 

 the centre of the tree, a very large quantity of air was dif- 

 engaged, but that none was difengaged when the inftrument 

 attacked the other parts of the tree. It is well known that 

 the medullary part, in which the air circulates particularly, 

 is fituated towards the centre. From this medullary part 

 proceed thofe tranfverfal vefiels which extend to the bark of 

 the tree for the circulation of the air. The plant contains' 

 alfo other vefiels for the circulation of the fap and of all the 

 Vegetable juices. There are alfo glands where the fecretion of 

 all ihefe different liquors is performed to produce the propolis, 

 pollen, bfc. A vegetable, therefore, in the fimpleft cafe, may 

 be coniidered as an ailemblage of feveral pliable elaftic fibres, 



compofing 



