19 2 THE FAEMER AT HOME; 



specific gravity of rain- water, and comparing all other bodies with this, 

 the same numbers that express the specific gravity of bodies, will at 

 the same time denote the weight of a cubic foot of each in avoirdupois 

 ounces, which is a great convenience in numerical computations. 



GRAZIER. In Agriculture, a term commonly applied to such 

 farmers as are engaged in the art and business of fattening various 

 sorts of live stock on pasture and other grass lands. That this sort of 

 business may be managed to the best possible advantage, the grazier 

 should have- a perfect knowledge of the nature, properties, and value 

 of all sorts of cattle and sheep stock, as well as of the quality of the 

 ground on which they are to be fed, and of the most proper methods 

 of suiting them to each other. And he should also be well informed 

 concerning the nature and states of markets in general. It is obvious 

 that upon those being well understood and properly regarded, much of 

 the success of this sort of farming business must depend, as thereby 

 proper advantage may be taken, not only of fairs and markets, but a 

 variety of other necessary circumstances. 



GREEN. One of the original colors excited by the rays of light. 

 The green color of plants has been shown, by the French chemists, to 

 depend upon the absorption of carbonic acid, and it is supposed that 

 the leaves of plants have the power of decomposing the carbonic acid 

 and water also. 



GREEN TURTLE. The most noted and the most valuable of 

 all animals of the tortoise kind ; by reason of the delicacy of its flesh 

 and its nutritive qualities, together with the property of being easily 

 digested. This animal, which is found in great abundance on the 

 coasts of Jamaica and some other West India Islands, is called the 

 green turtle from the color of its skin, which is rather greener than 

 that of others of the tortoise kind. It is generally found to weigh 

 about two hundred ; though some are five hundred, and others not 

 above fifty. Dampier tells us, of one that was seen at Port Royal, in 

 Jamaica, that was six feet across the back ; and that the son of Cap- 

 tain Roach, a boy about ten years old, sailed in the shell, as in a boat, 

 from the shore to \is father's ship, which was about a quarter of a 

 mile from land. 



GRINDING. In Cutlery, the operation of sharpening edge-tools. 

 This operation, as usually practised, is attended with no small incon- 

 venience, from the production of heat by friction. The heat produced 

 is so great, that hard tools are often softened and spoiled by the steel 

 becoming ignited during the grinding. To prevent this effect, the 

 grind-stone is partly immersed in a trough of water ; but in this case 

 the rotation of the stone must be moderate, and the work, of course, 

 slow, else the water will be thrown off by the centrifugal force. When 

 the water is applied from above by a cock, the quantity is too small to 

 counteract the heat, arid preserve the necessary low temperature. It 

 has even been found, that the edge or point of a hard tool ground 



