NIT 



NOS 



smell may be detected in cess-pools 

 and dunghills ; the carbonate and 

 muriate usually formed are volatile, 

 and escape into the air ; hence it is 

 recommended that charcoal be used 

 to absorb these substances, or that 

 sulphuric acid, gypsum, or green vit- 

 riol (sulphate of iron) be employed to 

 convert them into sulphates, which 

 are not volatile at ordinary tempera- 

 tures. Liebig asserts that an appre- 

 ciable amount of ammonia exists in 

 the air and rain storms, derived from 

 decompositions occurring on the 

 earth. Much of the fertility of de- 

 caying putrescent matters is said to 

 depend on the evolution of ammonia- 

 cal compounds, or the nitrates which 

 they originate by farther decay. 



In the compounds of ammonia with 

 bases, it becomes converted — accord- 

 ing to modern authorities — into an 

 oxide of ammonium, or N II4 0, or 

 an hydrate of ammonia ; hence, a ni- 

 trate of ammonia is, according to tliis 

 nomenclature, a nitrate of the oxide 

 of ammonium, N H4 O -[- N Os. The 

 nitrate, sulphate, muriate, and nu- 

 merous organic salts of ammonia, 

 have been found in plants. The sul- 

 phate, carbonate, muriate, and ni- 

 trate have been used as steeps in the 

 same way and dose as nitre, but are 

 too expensive in the commercial 

 form ; most of these are found in sta- 

 ble manure and putrescent composts. 

 The amount of ammonia taken by a 

 crop from an acre rarely exceeds 30 

 pounds, except in such crops as tur- 

 nips, cabbages, and cruciferous plants, 

 which often carry off upward of 100 

 pounds. Some plants evolve ammo- 

 nia from their leaves, and all throw 

 off nitrogen, which is most probably 

 derived from ammonia taken from 

 the soil. The common salts of this 

 alkali are all soluble, and decomposed 

 or volatilized at a red heat. 



NITRO. A prefix to the name of 

 bodies containing nitric acid or nitro- 

 gen. 



NITRO-MURIATIC ACID. Aqva 

 rcgia. A mixture of strong nitric 

 and muriatic acid, whereby chlorine 

 is evolved, which dissolves gold, pla- 

 tinum, and other metals. 



X s 2 



NITROUS ACID. A pungent, or- 

 ange-coloured, volatile acid, consist- 

 ing of one equivalent nitrogen and 

 four oxygen. 



NITROUS OXIDE. Protoxide of 

 nitrogen, laughing gas. 



N C T U R N A L. Of the night. 

 Many birds and insects prey only at 

 night. 



NODE. A knot or lump. A bony 

 tumour. The swelling on the stems 

 of plants where leaves start ; also 

 called nodi. A jiodal point, in physics, 

 is a place of rest, where several for- 

 ces counterbalance one another. 



NODOSUS. Knotty. 



NODULE. Rounded, irregular 

 lumps or masses. 



N G G I N G. In building, brick- 

 work carried up between uprights of 

 timber scantling. 



NOMENCLATURE. The lan- 

 guage employed in scientific descrip- 

 tions. 



NON-CONDUCTOR. A substance 

 incapable of conducting heat or elec- 

 tricity. 



NONESUCH. The black medic 

 ( M. lupuUna ), common in upland 

 meadows. 



NOOTH'S APPARATUS. A se- 

 ries of three glass vessels, placed ver- 

 tically, for the purpose of impregna- 

 ting water -with carbonic acid gas. 

 The lower vessel contains the mar- 

 ble and muriatic acid for the evolution 

 of the gas ; tiie central vessel holds 

 the water, through which it is made 

 to pass, under the pressure of the col- 

 umn of water in the third or upper ves- 

 sel, which is closed by a conical stop- 

 per, which serves as a safety-valve. 



NOPAL. The Opunlia cochimliif- 

 era, a cactus on which the cochineal 

 insect lives : native of the sandy 

 tracts of Mexico. 



NORDHAUSEN SULPHURIC 

 ACID. Fuming strong acid obtain- 

 ed by the distillation of green vitriol. 

 NOR M A L. Regular, straight, 

 usual. 



NOSE-BAG. A bag containing 

 corn or oats to be tied to the horse's 

 nose. 



NOSE-BAND. That part of the 

 headstall of a bridle which comes 



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