298 THE FARMER AT HOME. 



four or five days. After this, they open a hole made in one of the 

 sides of the pit, which lets out all the clear water into a channel 

 of about a foot wide, which is also lined with clay, and through 

 which it runs into a very wide and shallow pit, which is pre- 

 pared in a level ground, secured by slight walls on all but the 

 northeast side, and open to the sun at the top. Here the water 

 evaporates by degrees ; and the salt which it had imbibed from the 

 earth, cystallizes into small, brownish white, hexaedral. but usually 

 imperfect crystals. This is the rough saltpetre brought from the East 

 Indies. There are some other methods of procuring it ; but the far 

 greater part of the nitre used in the world, is prepared in this manner. 

 Saltpetre is of great use in various manufactures. Besides being the 

 basis of gunpowder, it is employed in making white glass, and is of 

 the same use as common salt in preserving meats. From the same 

 substance, also, are prepared Glauber's spirit of nitre, sweet spirit pf 

 nitre, vitriolated nitre, and aquafortis. 



NITROGBN. Nitrogen, also called Azote ; a substance existing 

 in great abundance, but is never found except in combination with 

 some other body. It is a principal component part of the air we 

 breathe, which consists of 78 parts of nitrogen, and 22 of oxygen. It 

 is accordingly here united with oxygen, and a certain portion of caloric 

 and light. The nitrogen and oxygen of the atmospheric air may be 

 separated, so that we may have the nitrogen by itself, but then only 

 in a state of gas, and its properties are very different from those of 

 the atmospheric air. Nitrogen gas will not support animal life. It 

 is a little heavier than atmospheric air, elastic, and capable of expan- 

 sion and condensation. It produces no change on vegetable colors, 

 and when mixed with limewater does not make it milky, as does 

 carbonic acid gas. Nitrogen gas and oxygen gas artificially mixed, 

 in proportions in which air is found in the atmosphere, have exactly 

 the same properties as atmospheric air, which they become, in every 

 respect. All animal and vegetable substances contain a large propor- 

 tion of nitrogen. 



NORMAN HORSE. It is not the design of the present work to 

 discuss the nice points resulting from the crosses of our best farm 

 animals. This is left for more elaborate treatises, and to persons more 

 competent to the task. We aim only at calling attention to some of 

 these most prominent points. By them it will be perceived that there 

 is a vast difference in the appearance and also in the merits of them, 

 and hence the great importance to our rural interests, that general 

 public attention should be directed to the subject. Of the horse fam- 

 ily there is much in the Norman branch to elicit observation. They 

 are of Arabian descent, and are much used in France, particularly for 

 drawing the heavy diligence coaches. The admired Canada horses 

 are more or less a mixture of this stock. A writer in the British 

 Quarterly Journal of Agriculture, sap, the Norman horses are capital 



