THE SOURCES OF THE NITROGEN OF VEGETATION, ETC. 563 



June 19. — One plant dead; another looking unhealthy; the third 4 to 5 inches high, 

 with five leaves, growing pretty well. 



June 26. — Two plants dead ; the other growing, 7 to 8 inches high, with nine leaves, 

 each with two stipules. 



July 3. — A pipette-ful of the phosphate-solution, and a pipette-ful of the sulphuric- 

 acid solution added. 



July 14. — The third or only surviving plant has ten leaves, but looks unhealthy. 



July 29. — The two dead plants fallen, moulded, and dried up. The other blackened 

 and mouldy at the base of the stem, and thence to the top yellow ; three top leaves 

 partly yellow, but the remainder black. 



August 17. — All three entirely dead. Pot removed, but products not analysed, as 

 there had not been sufficient healthy growth. It is difficult to account for this failure >* 

 but it is possibly due to the very hot weather. 



• 



No. 5. — Beans (1858); three seeds; prepared soil; without (but intended to have) 



nitrogenous manure. 



June 11. — Seeds set in prepared soil, with ash that had been neutralized with sul- 

 phuric acid, and gently re-ignited ; and the pot placed over sulphuric acid and covered 

 with a glass shade. 



June 21. — The pot removed to its place on the stand. 



June 26. — Three plants up ; green and healthy; four leaves, each with two leaflets, 

 and two stipules. Plants delicate, but healthy green colour ; one shows air-roots. 



July 3. — A pipette-ful of the phosphate-solution, and a pipette-ful of the sulphuric- 

 acid solution added. 



July 14. — Three plants, healthy and vigorous; 8 to 12 inches high; eight leaves on 

 each ; a few black specks on some of the leaves, otherwise healthy. The weather has 

 been comparatively cool since planting till now ; but now hotter with bright sun. A 

 few air-roots at the base of the stems. 



July 29. — Three plants ; 8, 8|, and 12 inches high. Plant (a) lost all its leaves, except 

 rudimentary ones at the top. A shoot 2 inches long with four small leaves about an 

 inch from the base, more growing than the parent plant ; another shoot appearing about 

 an inch above. Plant (b) very unhealthy ; lost all leaves but six small and partly black 

 ones at the top ; a vigorous shoot 5 inches long, springing an inch from the base, seems 

 to exhaust its strength ; another small shoot 1 inch long, about 2 inches higher up. 

 Plant (<?), most of the leaves dropped ; but several of the petioles remain, and are green ; 

 some small withering leaves at the top ; two shoots starting near the base. 



August 17. — Three plants; the main stem of each lost nearly all the leaves. Each 

 plant has living shoots with several leaves each near the base. 



August 23. — Plants taken wp: — 



There has been scarcely perceptible growth for two or three weeks ; leaves nearly all 

 off. Soil moist. Koots extend only a little way, and consist of a thick mat around the 



