202 



FORESTRY AND IRRIGATION. 



May, 



- OH-m'S'-'^'-'aT 



~Brs ss nt\^'' it\ ^^'^ 



DRAWING SHOWING SEWER-PIPE WATER MAIN AND NEW SLUICE HOSE. 



feet of lo-inch sewer pipe coming from 

 the factory, which we will lay through 

 the field, with hydrants conveniently 

 located, to which hose will be attached, 

 running across the field on each side of 

 the pipe line, for distributing water to 

 the furrows. In the accompanying 

 drawing the upper figure shows the 

 sewer- pipe main laid low enough to 

 avoid the plow, with hydrant made by 

 bringing water to the surface through a 

 Y and a one-eighth bend, with a short 

 piece of oiled hose attached (the hose is 



oiled in boiled linseed oil). The lower 

 figure shows the new sluice hose, the 

 ports regulated and closed by drawing 

 heavy hardware cord through brass 

 rings sewed fast and tied with one slip 

 loop, which will hold when wet. Rings 

 of large brass wire are sewed into the 

 ends of the hose and couplings made b}' 

 slipping one, laid horizontally, through 

 the other and straightening up inside. 

 The sluice hose (which is an original 

 device) seems to be meeting with favor 

 wherever tried. 



THE WORK IN DENDRO-CHEMISTRY. 

 By William H. Krug, 



Bureau of Chemistry, U. S. Department of Agriculture. 



CHEMISTRY is essentially a gen- 

 eral science, in that it has for its 

 object the study of the substances which 

 constitute the universe, the transforma- 

 tions of these substances, and the laws 

 which govern such changes. It is evi- 

 dent, therefore, that there are but few 

 special sciences of which chemistr}- is 



not an important and generally neces- 

 sary part. This is more full}' appre- 

 ciated when we know the extensive 

 specialization which has taken place 

 within the science itself, and most of 

 which is of comparatively recent origin. 

 The field is per se so large, and the in- 

 vestigations of the last fifty years have 



