No. 2. 



City Manures. — Disease in the Pear Tree. 



47 



also holds moisture with a tenacity greater 

 than any other known material. 



Our farmers may tell me they are well 

 aware of the value of urine, but may ask 

 how are they to collect it in sufficient quan- 

 tity. I have thought of this difficulty, and 

 believe it may be overcome by a little per- 

 severance. There is a small shed behind 

 the city hall, wliere many thousands of gal- 

 lons might be annually collected. Let some 

 farmer get the privilege from the corpora- 

 tion, of putting down a large receiver there 

 under ground, filling it half full of fine char- 

 coal, so as to take off the powerful effluvia — 

 now so offensive — on condition of its being 

 emptied twice a year, spring and fall. Let 

 the same system be pursued at all the large 

 eating houses and taverns. Instead of such 

 places being as now, injurious to the health 

 of the neighbourhood, they would become 

 perfectly sweet and inocuous. The diffi- 

 culty would be greater in families ; yet if it 

 can be proved that those who inhabit houses 

 can derive an annual income from attending 

 to it, as well as take off all bad smells from 

 every square in the city, I should presume 

 the double inducement would cause the sys- 

 tem to be generally adopted. The greater 

 portion of the urine of families is daily 

 thrown into the privies. If every family 

 would have theirs emptied once a year, and 

 when emptied, put into the vault two barrels 

 of charcoal, and add one barrel of charcoal 

 every month afterward, at the end of each 

 year they would have about forty bushels of 

 poudrette and urate, of a far better quality 

 than any now sold, worth twenty-five cents 

 per bushel, to the person who may take it 

 away, exclusive of the expense of removal. 

 Thus every family might make a clear in- 

 come of eight dollars per annum, beyond the 

 cost of the cliarcoal, and keep the whole city 

 free from the abominable excrementitious ef- 

 fluvium now so pernicious to the health and so 

 obnoxious to the olfactories of our citizens. 



It will be seen that carbon and oxygen 

 form eight and a half parts in every ten of 

 vegetable matter, and it is more than proba 

 ble that carbonic gas supplies the whole of 

 it. How amply has Infinite Wisdom pro- 

 vided for this immense demand! Can the 

 geologist measure the carbonate of lime and 

 other carbonates laid up by Creative Wis- 

 dom in our globe"? Can the physiologist 

 count the weight of carbonic gas daily ex- 

 haled by the animal creation? Can the phi- 

 losopher form a distant conception of the 

 immense supply hourly liberated by the rapid 

 and slow decomposition ever progressing on 

 our earth's surface! If man has not the 

 power to measure or count the supply, he 

 has given to him the power to collect and 



apply it for his individual and general 

 benefit. 



It was my intention to have explained, 

 in this essay, the effect of lime in promoting 

 vegetation when mixed in soils, as hinted 

 when treating of its operation on saw-dust; 

 but as this article is already too extended, I 

 shall defer it to some future opportunity. 

 Wm. Partridge. 



Disease in the Pear tree. 



For many years past, the pear tree has 

 been found to be subject to a peculiar mala- 

 dy, which shows itself during midsummer, 

 by the sudden withering of the leaves and 

 fruit, and the discolouration of the bark of 

 one or more of the limbs, followed by the 

 immediate death of the part affected. la 

 June, 1816, the Hon. John Lowell, of Rox- 

 bury, discovered a minute insect in one of 

 the affected limbs of a pear tree ; afterwards 

 he repeatedly detected the same insects in 

 blasted limbs, and his discoveries have been 

 confirmed by Mr. Henry Wheeler and the 

 late Dr. Oliver Fiske, of Worcester. Mr. 

 Lowell submitted the limb and the insect 

 contained therein, to the examination of 

 Professor Peck, who gave an account and 

 figure of the latter, in the fourth volume of 

 the " Massachusetts Agricultural Repository 

 and Journal." From this account, and from 

 the subsequent communication by Mr. Low- 

 ell, in the fifth volume of the " New Eng- 

 land Farmer," it appears that the grub or 

 larva of the insect, eats its way inward, 

 through the alburnum or sap-wood, into the 

 hardest part of the wood, beginning at the 

 root of a bud, behind which, probably the 

 egg was deposited, following the course of 

 the eye of the bud towards the pith, around 

 which it passes, and part of which it also 

 consumes; thus forming, after penetrating 

 through the alburnum, a circular burrow or 

 passage in the heart-wood, contiguous to the 

 pith which it surrounds. By this means, the 

 central vessels, or those which convey the 

 ascending sap, are divided, and the circula- 

 tion is cut off. This takes place when the 

 increasing heat of the atmosphere, producing 

 a greater transpiration from the leaves, ren- 

 ders a large and continued flow of sap ne- 

 cessary to supply the evaporation. For the 

 want of this, or from some other unexplained 

 cause, the whole of the limb above the seat 

 of the insect's operations suddenly withers, 

 and perishes during the intense heat of mid- 

 summer. The larva is changed to a pupa, 

 and subsequently to a little beetle, in the 

 bottom of its burrow, makes its escape from 

 the tree in the latter part of June, or begin- 

 ning of July, and probably deposits its eggs 



