148 BOTANY. 



sheets of brown paper. In humid countries and 

 seasons, it is desirable to accelerate their desicca- 

 tion by an artificial heat. For that purpose, we 

 put a number of plants between tw r o planks, separ- 

 ated from each other by two or three sheets of 

 paper, we place this packet in a stove or oven, 

 after the bread is taken out; this quick method 

 does not even alter the colours. When they are 

 dry, we change the paper. There are some plants 

 which are very watery, such as bulbous plants, or- 

 chideae, &c. and which continue to vegetate in the 

 herbals several months after they have been placed 

 there. When these plants are gathered in the state 

 in which we wish to preserve them, w r e plunge them 

 for a minute into boiling water, then put them be- 

 tween two leaves of brown paper ; they will after- 

 wards dry quickly, as the action of the boiling 

 water will have destroyed the life of the plant. 



On each packet of plants of the same species, 

 we put a note, indicating the name the plant bears 

 in its own country, the height of the country above 

 the level of the sea; in short, the same notes which 

 we have required for living vegetables. These in- 

 structions are extremely important for the geo- 

 graphy of plants, to the progress of which, Hum- 

 boldt has so much contributed. It is also useful to 

 notice the height of the plant, the colours of its 

 flowers, and the odour they exhale, as these cannot 

 always be learned from a herbal. 



