368 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



time, the cambium of the scion unites perfectly with that of 

 the stock. The place of this union remains visible, and is 

 named by Mr. Gceppert the line of demarkation. All devel- 

 opment above this line belongs to the scion, all below to the 

 stock. The stock, entirely deprived of leaves, furnishes, as it 

 w T ere, the crude sap to the scion, which, by its organs of veg- 

 etation, assimilates it. But as soon as the descending sap 

 has passed the line of demarkation it assumes again all the 

 peculiarities due to the nature of the stock, and as no leaves 

 are allowed on the stock to elaborate the sap, it appears that 

 the thin stratum of tissue formed at the connection is the 

 only means of producing this change, and thus retaining the 

 characteristic distinctions of scion and stock. Such mutual in- 

 dependence is also often seen in the difference in growth, the 

 stock frequently surpassing the scion, and inversely. 19 (7, 

 vii., 1872, 112. 



action of salt of potash on vegetables. 



Considerable interest was excited some months ago by 

 the detail of experiments prosecuted by Dr. George B. Wood 

 upon the action, of salts of potassa on vegetation. In a sub- 

 sequent communication to the American Philosophical Socie- 

 ty, he states that, in a field of grain devoted to these experi- 

 ments, the soil of which was previously exhausted by bad 

 culture, one half was enriched by barn manure, and the other 

 half with similar manure with the addition of a certain quan- 

 tity of wood ashes. The effect of the latter application was 

 especially marked, the yield being much greater than with 

 the former. The most striking results were obtained by the 

 use of ashes of the poke-berry (Phytolacca decandra). Pr. 

 Am. Ph. /Soc, February 2, 1872. 



POWDERED COAL FOR UNHEALTHY PLANTS. 



In a communication addressed to the Revue Jlortlcole, the 

 writer states that he purchased a very fine rose-bush, full of 

 buds, and, after anxiously awaiting their maturing, was great- 

 ly disappointed, when this took place, to find the flowers 

 small, insignificant in appearance, and of a dull, faded color. 

 Incited by the suggestion of a friend, he then tried the ex- 

 periment of filling in the top of the pot around the bush, to 

 the depth of half an inch, with finely-pulverized stone-coal. 



