88 Mrs. Ibbetson on the injurious Effects [August, 



more different, yet they reason as if the same operations took 

 place in both ; whereas the first effect to be produced on the 

 recent plant is to kill it, a process of no small difficulty ; while 

 the vegetable matter in the manure is certainly dead. It has 

 passed through the stomach of the animal, has been exposed 

 there to a high temperature, and yet often without being entirely 

 decomposed ; since considerable quantities of straws and clover 

 stalks will be found in dung not yet digested, though exposed 

 not only to such heat, but to the dissolving power of the gastric 

 juices. How then can we expect that the earth (so cold in com- 

 parison) will so soon decompose the vegetable matter, and what 

 would be a still greater miracle, convert it into mould, when it 

 has only that sap to assist in its decay, which certainly possesses 

 no digestive or reducing powers? So far indeed are the vege- 

 tables when placed in the ground from making manure, that as 

 soon as the part of the stem which is opposite a branch touches 

 the earth, roots are directly nourished, and soon protruded ; and 

 let the process of decay proceed ever so far before they are 

 buried, it is directly stopped, and the earth is sure to arrest its 

 progress instead of accelerating the decomposition. 



I have now dug up another trench, which has been preserved 

 since last May,* and not opened till the 1st of the present 

 month ; it fully confirms all I before made known respecting the 

 excessive duration of vegetable life, with many curious circum- 

 stances that greatly assist me in the acquirement of a more 

 perfect knowledge of plants ; while they confirm many of the 

 most important points that I have before ascertained by means 

 of dissections, and advanced on vegetable physiology. 



All the weeds natural to the soil, and the herbaceous plants, 

 were growing again, sickly, though firmly ; many of them even 

 piercing the earth, and appearing just shooting above, and 

 throwing out fresh germs, except the conium maculatum, 

 which I have always found to die in the leaves, though not 

 in the root. I this time made a thorough trial of fresh aquatic 

 plants; as they decay so immediately on being taken out 

 of the water, I supposed they would die still quicker under 

 ground, and would of course form an excellent manure. I, 

 therefore, buried several plants of potamogeton and ranun- 

 culus aquatilis, which both appeared to decay as soon as 

 taken from the water ; the pit was opened four months after 

 burying them, and they were perfectly alive, the first fermenta- 

 tion having stopped the moment they entered the earth ; so that 

 they appeared as fresh as when they had been taken out of the 

 water only for a very few hours. This plainly shows that there is 

 no trusting to any thing but experimental knowledge ; for though 

 a part of these plants had really begun to decay before they were 

 placed in the earth, yet the fermentation was directly arrested ; 



* May, 1817. 



