JULY. 



349 



As soon as the cuttings are rooted, which may be known by their appear- 

 ance of growth, they must be potted off; but care must be taken not to 

 injure the roots, and they must be shaded again for a week or ten days, 

 until they make fresli ones ; they must then be gradually hardened, and 

 placed with the old plants in the greenhouse. — (Card. Chron.. 1855, p. 317.J 



Leaves from my Chinese Note-Book. — Chinese Yam (Dioscorea Ba- 

 tatas.) — This esculent seems to be attracting a good deal of notice in 

 England as well as in France, and is apparently considered by some per- 

 sors equal, if not superior, to the potato itself. It is very abundant in China 

 but is not a staple crop, like the sweet potato, for example. Foreigners, as 

 a body, prefer it when roasted to the sweet potato ; but do not dream of 

 putting it on a par with the common potato. However, I believe there is 

 no vegetable of the kind at present known more likely than this is to take 

 the place of our old favorite, providing it should die out or become so dis- 

 eased as to render its cultivation uncertain, and consequently unprofitable. 

 In making this assertion, I am taking for granted that the climate of En- 

 gland is suitable for the production of the Chinese Yam, which I must 

 confess I have some doubts about. I dare say it will prove hardy enough 

 to withstand an English winter, but are our summers hot enough'? or does 

 not the want of summer heat account for Mr. Thompson's failure in the 

 garden of the Horticultural Society ? Experiments made in glass frames, 

 or with bottom heat, or even in the open air in a summer which may be 

 unusually warm, are all to be guarded against in deciding an important 

 question of this kind. It ought to be kept in mind that the sweet potato, 

 the Arum esculentum, the Nelumbium speciosum, and such like plants, are 

 cultivated as esculents in the north-eastern provinces of China, along with 

 the yam. But should the summers of England prove warm enough for 

 its cultivation, I have no hesitation in saying that it is more likely to suit 

 the tastes of the people than anything which has been brought forward 

 since the commencement of the potato disease. 



Mosquito Tobacco. — Some amusing correspondence has appeared upon 

 this subject, which I cannot take as very complimentary to my last book, 

 "A Journey to the Tea Countries," &c., or to the retentive memories 

 of the readers thereof. Mr. Prideaux says, (Sept. 9th), " In answer to 

 ' R. A. H.' respecting the passage referred to in Fortune's book on China, 

 I have made the following note, unfortunately without the reference. ' For 

 keeping offmusquitos, the Chinese use the resinous saw-dust of the juniper 

 smeared upon bamboo, which they find very efficacious.' " Dr. Hooker 

 states " he has somewhere read or heard of the plant in question being a 

 species of artemisia." The following passage, quoted from the book in 

 question will assist the memories of both correspondents, although it will 

 not add much to our information. " Various substances are employed by 

 the Chinese to drive away mosquitos. This which we had just purchased 

 was made from the sawings of resinous woods — I believe procured from 

 juniper trees — and mixed with some combustible matter to make it burn. 

 A piece of split bamboo, three or four feet in length, is then covered all 



