252 ELEMENTS OP BOTANY. 



Assorted corks and rubber stoppers. 



Microscope slides. 



Thin glass covers. 



Thin sheet rubber, such as is used by dentists, in pieces about 24 

 inches square (this is not needed i£ the teacher prefers to use sheet 

 lead in the transpiration experiment; see page 115). 



General Reagents and other Supplies. — Alcohol, commercial, 95%. 



Alcohol, absolute, a few ounces only. 



Hsematoxylin solution.^ 



Canada balsam. 



Caustic potash solution, one part of solid caustic potash in 20 

 parts distilled water. 



Mtrie acid, concentrated. 



Red ink.2 



Potassium chlorate. 



Fehling's solution, test for grape sugar. This reagent may best 

 be bought of the wholesale druggist or dealer in chemicals. It may 

 be prepared by dissolving 34.64 grams pure crystallized cupric 

 sulphate in 200 cubic centimeters water and mixing the solution 

 with 150 grams neutral potassic tartrate, dissolved in about 500 

 cubic centimeters of a 10-perK3ent solution of sodium hydrate. The 

 whole is then to be diluted with water to 1 litre and 100 cubic centi- 

 meters glycerine added. 



Millon's reagent for proteids. Prepared by dissolving 1 part by 

 weight of mercury in 2 parts of nitric acid of sp. gr. 1.42 and then 

 diluting with twice its volume of water. 



Preservative fluid, prepared by dissolving 20 parts by weight of 

 chrome alum and 5 parts formalin in 975 parts of water. This 

 serves to preserve (although it may discolor) portions of leaves, 

 stems, rootstocks, roots, fruits, etc., which it is desirable to keep in 

 a moist condition, and is much cheaper than alcohol. One part 

 formalin to 40 of water by volume makes a stiU. better preservative 



• It is cheaper to buy this than to make it. 



2 As considerable quantities of this are to be used (especially if it is issued to the 

 class for home work), if it cannot be bought very cheaply the instructor may make it 

 for himself by dissolving eostn in water. Eosin costs by the pound from J1.65 to 

 $2. An ounce will make as much as two quarts of red ink. 



