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REPORT ON THE INDUSTRY OF MANURES. 
Early History of Manures .■—Manures, in the form of cattle-dung and ordinary farm¬ 
yard composts, have been known and employed from time immemorial for the ferti¬ 
lization of the soil; but the manures termed, “artificial,” which have their origin 
elsewhere than in the farm itself, and are for the most part of concentrated and portable 
character, have but of late years come largely into use. Nevertheless, the manufacture 
of these manures, and the trade to which they have given rise, already rank amongst the 
most extensive of modern industries. 
The British patent-rolls record the grant, previously to 1800, of only three patents for 
manures, dated respectively 1721, 1729, and 1773 ; whereof the last only, taken out by 
Baron van Haake, was duly specified. The claim in this case is for a composition of 
common salt, saltpetre, lime, and Rhenish tartar, which is declared to “ possess a mag¬ 
netic quality, whereby it attracts fertility, and is productive of the effect of manuring 
arable land,” etc. 
This curious specification affords a rough measure of the state of popular knowledge 
and opinion on the subject of manures towards the end of the last century. 
The first manure-patent of the present century was granted, in 1802, to one Estienne, 
for a method of converting human excrement into manure, by gathering it in tanks, de¬ 
canting its liquid part, drying the solid sediment in the sun (with or without addition of 
lime), letting this ferment in heaps, and finally crushing it to powder. This was a step 
in the right direction ; though we now know that the treatment suggested, by removing 
frpm the compost all its soluble and volatile ingredients, must have destroyed nineteen- 
twentieths of its value. 
In 18'06, pounded oyster-shells and gypsum were patented, as a fertilizing mixture, by 
John Fletcher. This was also a fair proposition. Oyster-shells are slightly phosphatic, 
and gypsum is known to benefit many soils. 
After these slight efforts, invention in this department seems to have slept during 
more than a quarter of a century; for the next manure patent on record bears date 1835. 
In that year, one Pottevin patended a compost of nightsoil with calcined river or pond 
mud, or other carbonaceous earth. This was a great improvement on Estienne’s proposal; 
seeing that the mud, charred by calcination, and brought to a porous, absorbent condition, 
would tend to retain and partially disinfect the fertilizing matters, which Estienne’s 
mode operated to volatilize or wash away. 
Hence it appears that the first third of the present century produced as many manurial 
inventions as the whole of the preceding century, and that the inventions produced had 
improved in character and value, as well as in rate of development. Still there was little 
to boast of; and half-a-dozen projects, comprising two of moderate utility, represented 
our total progress in this art (as measured by the patent records) some five-and-twenty 
years ago. 
Course of Early Scientific Research. —In the meantime, however, a vast store of 
scientific information, tending more or less directly to the elucidation of this important 
subject, had been in slow and silent course of accumulation, by the successive labours of 
many eminent experimentalists. 
Not to go back further than the last century, nor even than its latter half, we shall 
find, concentrated in this brief period, a series of brilliant discoveries, bearing more or 
less directly upon the manurial and agricultural questions, but far too numerous even for 
the most cursory narration here. Space would fail us even to enumerate the names of 
European celebrity that adorned this memorable epoch ; but if we had to select half-a- 
dozen of the most illustrious to represent the philosophical activity, British and con¬ 
tinental, of the period, we "would venture to single out on the one hand, Black, Priestley, 
and Cavendish: and on the other, Lavoisier, De Saussure, and Berthollet. 
During the fifty years in question the nature and composition of air and water , of car¬ 
bonic acid and ammonia (the four main forms of volatile plant-food) were discovered, 
their gaseous elements isolated, and their properties determined. 
The sciences of geology and meteorology at this period also began to take shape and 
form ; enabling an inside to be gained into the origin and nature of cultivable soils, and 
into the climatic conditions of plant-growth. 
At the same time the laws of the physical forces, particularly those of light and heat, 
began to be better understood, as well in their general relations as in their special in¬ 
fluence on plants. 
The introduction of more accurate chemical methods permitted, meanwhile, a closer 
