346 Plants in Sleeping Rooms. 



the London season, his reception rooms are crowded with per- 

 sons eminent ibr their learning and talents, not only English- 

 men, but foreigners. It is impossible for any person to be 

 more kind and liberal than is Mr. Lambert, with all this 

 power to oblige. His books and »Jiis herbarium are always 

 open to the use of all literary persons, and many important 

 works have owed their origin and progress to him. " Without 

 the herbarium of Mr. Lambert,' 1 says Loudon, in the preface to 

 his great Encyclopedia of Plants, " this work could not have 

 been completed." A large number of the excellent wood-cuts 

 with which that useful book is illustrated, were engraved from 

 specimens in Mr. Lambert's collection. His librarian is, or 

 was, David Don, Esq., whose botanical publications are well 

 known. 



PLANTS IN SLEEPING ROOMS. 



It is not many months since a case was reported of the 

 death of a lady, supposed to be caused by her sleeping in a 

 close room which contained a number of plants. This was pro- 

 bably the true cause of the catastrophe, and its explanation on 

 chemical principles, is not difficult. It has been stated in one 

 of our articles on Vegetable Physiology, that carbonic acid gas, 

 a very deleterious substance, is absorbed from the atmosphere, 

 and decomposed by the leaves of plants, when under the in- 

 fluence of a strong light — oxygen being at the same time 

 evolved. Now the process of human respiration produces an 

 effect exactly the reverse. The lungs decompose the atmos- 

 pheric air, but retain its oxygen, which acts upon the blood, 

 while the carbonic acid is evolved. Thus plant? in rooms are 

 rather beneficial than otherwise by day, since they then absorb 

 the carbonic acid produced by breathing the air, and leave the 

 oxygen. But in the darkness of night, the process is reversed. 

 Their leaves then give out carbonic acid gas, and retain oxygen. 

 A superabundance of the former gas always produces stupor, 

 head-ache, and a sense of suffocation in those who breathe it, 



