50 



A DISCOURSE 



corn-fed birds, so eminently effectual before tlie soil of horses and other 

 beasts, in which it less abounds, as having less virtue to attract it 



It is salt that gives such vigour to places sprinkled with urine, soot, 

 ashes, &;c. which have them not diluted ; and to bones, flesh, horn, hair, 

 feathers, blood, and the rest of those animal excrements : and whence 

 those seminal masses should proceed after calcination of the earth, when 

 it comes to be exposed again, is hard to divine; whence, I say, they should 

 derive their life and energy, without being destroyed by so powerful an 

 agent as fire, unless they lurk in some vegetant and indissoluble salts, (vo- 

 latile, fixed, or nitrous earth,) from whence they (phoenix-like) emerge, 

 though I do not say without any other specific rudiment : but it is 

 strange, what, as I remember Dr. IMorison affirms of the Enjsimum, or 

 Irio, so seldom seen to grow spontaneously in England before the late 

 prodigious conflagration of this city, when there appeared more of it 

 amongst the ruins, than was known to grow in all Europe besides : it 

 being a curious exotic, to be found most about Naples in the time of 

 Fabius Columna, and but rarely elsewhere ^ 



It is salt which resuscitates the dead and mortified earth, when, lan- 

 guishing and spent by indulgence to her verdant offspring, her vigour 

 seems to be quite exhausted, as appears by the rains and showers which 

 gently melt into her bosom what we apply to it, and for which cause 

 all our composts are so studiously made of substances which most en- 

 gender or attract it. 



' The richness of poultry and pigeon dung appears ratlier to arise from its being over- 

 charged with oil and mucilage, than any thing saline. For further information upon this 

 subject, consult the note upon the 27th page of the 1st vol. of the Silva. 



^ This is the Sisymbrium ( Irio ) foliis nincinatis dentatis nudis, caule Icevi, Jiliquis erectis. 

 Linn. Two years ago a crop of wild mustard ( Erysimum vulgare. Bauh.) was reaped from the 

 banks raised at Hull to form a dock for the reception of shipping ; and it is generally ob- 

 served that a spontaneous crop of this vegetable makes its appearance, for two successive 

 years, upon the banks of all large drains made in Holderness. Similar appearances have 

 been observed in the isle of Axholme, and other low countries. This phsenomenon proves 

 that seeds, when kept from air, may retain their vegetative power many years beyond the 

 term seemingly allotted them. 



