234 



of deinarkation it assumes again all the peculiarities due to tlie 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 produciag this change and thus retaining the char- 

 acteristic distinctions of scion and stock. Such mutual independence 

 is also often seen in the difference in growth, the stock frequently sur- 

 passing the scion, and inversely. 



The number of eggs from a hen — A German naturalist answers 

 the question how many eggs a hen can possibly lay, as follows: The 

 ovary of a hen contains about six hundred embryo eggs, of which, in 

 tbe first year, not more than twenty are matured. The second year 

 produces one hundred and twenty ; the third, one hundred and thirty- 

 five; the fourth, one hundred and fourteen; and in the following four 

 years the number decreases by twenty yearly. In the ninth year only 

 ten eggs can be expected, and thus it appears that after the first four 

 years hens cease to be profitable as layers. 



Amount and origin of mineral matter in plants. — Baudri- 

 mont, in the course of an examination into the amount of mineral 

 matter in plants, determined the composition of quite a number of • 

 species, and arrived at the following conclusions: First, that mineral 

 matter is found in all plants, even in those of aerial growth, which would 

 scarcely seem likely to have the power of acquiring it ; second, that the 

 mineral matter contained in plants occurs in at least two distinct con- 

 ditions, namely, as a simple solution in the vegetable juices, either not 

 having been yet utilized or unassimilable as the product of dejection, 

 or else as finally united to or fixed with organic matter ; third, this latter 

 mode of union may occur in variable proportions, from the smallest 

 quantity indispensable to the production of organic matter to a maxi- 

 mum, "where the reciprocal action becomes zero. 



The variability of the relatis^e proportion of the organic mineral mat- 

 ter shows that these are not united to each other, as the fundamental 

 chemical elements are united. In place of an intimate combination in 

 definite proportions between the elements of molecules, there is only a 

 simple adhesive union, with the preservation of the fundamental struc- 

 ture of organic products. 



Baudrimont was much struck by finding that Cactus permianies con- 

 tained 94 per cent, of water and volatile matter, and .04 per cent, of or- 

 ganic matter ; and, therefore, that .05 per cent, of organic mineral matter 

 ■was sufficient to give this plant a definite form, and a texture which 

 enables it to resist atmospheric agencies. 



Properties of eucalyptus. — An elaborate essay upon the Euca- 

 lyptus appears in the October number for 1871 of the BuUetin of the 

 Acclimation Society of Paris, as prepared by M. Eaveret-Wattel. In 

 this the merits of the tree for many purposes are detailed at length. 



Utilization of suint. — In nothing is the spirit of the age more 

 clearly shown than in the eftbrts made to utilize waste substances. 

 This is being done with such efl'ect that what was formerly got rid of 

 with great difiiculty and at considerable expense may become one of 

 the most important objects of manufacture. We need only point to 

 such matters as sewage, the slag of furnaces, the fine coal of com- 

 merce, the waste of pyrites used in the manufacture of sulphuric acid, 

 &c., as illustrations. Quite a recent instance of this improved economy 

 is found in the treatment of the wool of sheep. It has been ascertained 

 that sheep derive from the soil upon which they pasture a considerable 



