THE BEE-KEEPERS' REVIEW. 



135 



us to understaiul this. See Johnston's 

 "How Plants I'eed," for an exhaustive 

 treatment of this subject. 



I set out with the statement, then, that 

 the atmosphere is the indirect source of 

 both hone}' ami honey dew; thi.t these 

 two articles are nearly identical; the only 

 difference being that the honey in the 

 course of its elaboration indjibes from the 

 flowers of plants and trees a portion of 

 their aroma — which is always wanting in 

 honey dew. To make this at all clear, it 

 will be necessary to briefly advert to the 

 composition of the atmosphere and to the 

 elaboration of plant food from its ele- 

 ments. 



The general composition of the atmos- 

 phere is familar to all. It is chiefly made 

 up of two gases — oxygen and hydrogen, 

 which are present in nearly equal propor- 

 tions. While the.se play an important 

 part in vegetable growth, it is the carbonic 

 acid of the atmosphere that is the 

 basis of vegetable ti.ssue, and the source 

 of honey and honey dew. The propor- 

 tion of this element is only one twen- 

 ty-five thousaudth of the bulk of the 

 atmosjdiere. Its chemical formula is C, 

 C)-', which means that it consists of 

 one atom of carbon and two of oxygen. 

 As it is the carbon of this gas that largely 

 enters into the tissue of trees and plants, 

 and as it forms such a small proportion of 

 the volume of the atmosphere, it is con- 

 soling to know that the best authorities 

 say that 2.S tons of carbon is carried by 

 that amount of air which rests over each 

 square acre of the earth's surface. As 

 not one-third of the earth's surface is 

 covered vegatation, and the air is ever in 

 in motion, the local supply is ever renew- 

 ed; and what is being exhaused in plant 

 food is restored by cumbusti(jn and the 

 perpetual decay of vegetable matter. 

 Thus the equilibrium is, and will be 

 maintaineil — another evidence of "the 

 economy of nature. " 



Having .stated that carbonic acid is the 

 indirect .source of honey dew, and glanc- 

 ed at its presence and proportion in the 

 atmosphere, it now remains for us to con- 



sider how it is appropriated by the vege- 

 table world, transmuted into that which 

 goes to make up the greater part of its 

 product.s — honey dew among the rest. 



It is enough for our purpose to say that 

 the outer skin or epidermis of the leaves 

 and green shoots of trees and plants are 

 studdeil with minute cells — inspiratory 

 and respiratory organs. It is estimated that 

 these range from 800 to 170,0003 to the 

 square inch in various plants. The carl)on- 

 ic acid of the atmo.sphere is inhaled 

 through the.se pores, and under the influ- 

 ence of light, heat, moisture, and other 

 agences; undergoes various tranformations 

 in the sap-cells beneath. During the pro- 

 gress of digestion there are several well 

 marked changes that take place in plant- 

 food thus inhaled. The first is the fixation 

 of carbon. This again istransnmted into 

 starch; the starch into sugar, which, in 

 turn, is converted into what finally goes 

 to form wood tissue. (See Gray's Struc- 

 tural Botony. ) From the Saccharine 

 stage of digestion comes our honey and 

 honey dew. The former is in some man- 

 ner, as yet, unexplained, determined to 

 the flower, while the latter is the result of 

 the sap-cells, under certain atmospheric 

 conditions, becoming gorged, when a por- 

 tion of the sweet juice they contain ex- 

 udes through the pores of the leaf and 

 green shoot, and rests on their surfaces — 

 hence our honey dew. 



Thus weseethat Mr. Cowan's definition 

 is the correct one; namely; "A saccharine 

 substance, or sweet juice, which at times 

 and under certain atmospheric conditions 

 exudes from the surface of the leaves of 

 trees and plants." 



The difference in color it sometimes 

 presents, may be, in part, accounted for 

 by the smnt Prof. Cook speaks of; but it 

 is more likely to l)e the presence of aphides 

 in great numbers which at times are 

 found devouring it, and that the inferior 

 quality of the article is the re.sult of its 

 being largely mixed with the excreta of 

 these insects — such stuff when stored in 

 the hive is unfit food for either man or bees. 

 Owen Soind, Out., Feb. 20, 1S99. 



