OB 



OCT 



much cheaper. Some men, who 

 keep many horses, cut all the hay 

 into chaff by a machine, and, mixing 

 this with a proper proportion of oats, 

 feed all their horses in mangers with 

 a ccrtam allowance of the mixture, 

 a practice much more economical 

 than that usually adopted. In France 

 and Germany the practice of baking 

 oats, as \\ell as rye, into loaves for 

 horse food, is gaining ground, and is 

 said to be attended with an evident 

 saving of food." 



The oat is a pretty sure crop ; the 

 smut and chincli-bug sometimes re- 

 duce the yield, and rust impoverishes 

 the straw ; but as these enemies 

 come late, it is best to cut the crop 

 as early as they appear : the wire- 

 worm sometimes destroys a portion. 



OATS, COMPOSITION OF. The 

 general composition of the oat is sim- 

 ilar to the other cerealia, and the spe- 

 cial compost given for wheat will 

 serve for this crop and for barley. 

 By Boussingault, the yield of an acre 

 perfectly dry in grain is 975 pounds ; 

 straw, 1176 in the dried state (small 

 crop) ; the ashes, 4 per cent, grain, 

 5 1 straw, or, per acre, 39 pounds 

 for the grain, and 60 pounds for the 

 straw. The composition of the ash, 

 per cent., was, 



Grain, Straw. 



Potash 12-9 243 



Soda 00 4-4 



Lime 3-7 8 3 



Magnesia 7-7 28 



Phosphoric acid 14-9 3-0 



Sulphuric acid 10 41 



Silica 53-3 400 



Chlorine 0-5 4-7 



Irou, carbonic acid, and loss . 6°0 83 



1000 100-0 

 It would appear, therefore, that bone 

 earth, common salt, gypsum, and, 

 where the composition can be formed 

 at little expense, silicate of potash, 

 would be excellent manures, and 

 might be combined in compost with 

 nitrate of soda. 



The ultimate composition of the 

 grain gives 2 24 per cent, nitrogen ; 

 the straw, 38 ; and, according to the 

 Scotch, 14 pounds of oats yield eight 

 of meal. 



OB. A very common affix to de- 

 scriptive words in botany, &c., as 



Y r 



[ obcordate, obrotund, &c., signifying 

 nearly or somewhat heart-shaped, 

 round, &c. 



OBESITY. Extreme or morbid 

 fatness. 



OBJECT GLASS. The glass, or 

 lens, of the telescope nearest the ob- 

 ject. 



OBJECT STAFF. The survey- 

 or's staff. See Levelling- Staff. 



OBLaTE. Somewhat spherical, 

 but flattened in the perpendicular ax- 

 is, as an orange, the world. 



OBSIDIAN. A black, glassy, com- 

 pact lava, consisting of potash and 

 soda, 7 to 10 per cent. ; silica, 7750 ; 

 alumina, 1175; iron, 1-25. 



OBTUNDENTS. Mucilaginous, 

 oily, or bland substances, which re- 

 duce the acrimony of other medi- 

 cines. 



OCCIPITAL BONE. The bone 

 which forms the back portion of the 

 skull, to which the spinal column is 

 attached. 



OCHRE. Peroxide of iron mixed 



with clay : the colour is very durable. 



OCHREA. The leaf-stems which 



clasp or surround the stem, as in the 



case of some grasses. 



OCTAGON. A superficial figure, 

 with eight sides or angles. 



OCTAHEDRON. A solid, with 

 eight regular sides; it is one of the 

 most common figures of crystals, and 

 may be a derivative from the cube or 

 tetrahedron. 



OCTANDRIA (from oktu, eight, 

 and avrjp, male). The Linnsan class, 

 in which the flowers contain eight 

 stamens. 



OCTOBER. This is one of the 

 most important months. Whenever 

 frost begins to occur, all tender roots 

 and potatoes should be stored. Ap- 

 ples, pumpkins, and other fruits are 

 also to be stored. Turnips, parsnips, 

 and carrots may remain in the ground. 

 Hemp, sugar, tobacco, and cotton 

 are either quite or nearly collected. 

 This month is also preferred for tim- 

 ber cutting. Wheat sowing, as well 

 as winter grains, should be draw- 

 ing to a close, as the season is late 

 except for the South. In the garden 

 and orchard, transplanting and prop- 



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