| Summary: | Newsletter of the North Dakota School for the Deaf. The North Dakota Banner, VOL. VII. Devils Lake, N. D., September 18, 1897. No. 1. BABY HAS GONE TO SCHOOL. Mortar is used to unite bricks and The baby has gone to school. Ah, me! What will the mother do, With never a call to button or pin Or tie a little shoe? How can she keep herself busy all day With the little hindering thing away? Another basket to fill with lunch, Another “Goodby!" to say, And mother stands at the door to see Her baby march away And turns with a sigh that is half relief And half a something akin to grief. She thinks of a possible future morn When the children, one by one, Will go from their home to the distant world To battle with life alone And not even baby be left to cheer The scattered home of that future year. She picks up the garments here and there Thrown down in careless haste And tries to think how it would seem If nothing were displaced. If the house were always as still as this, How could she bear the loneliness? —Exchange. BUILDING STONES.* The name limestone is applied to all rocks which are composed principally of carbonate of lime. Rock of this description is found in all parts of the world. Common limestone is used as a building material. Carbonate of lime is frequently found in rivers, seas, and lakes. When water from these seas, etc., is evaporated, carbonic acid passes off, and the carbonate of lime remains. The projecting and hanging stones of irregular shape which decorate the walls of limestone caves are deposits of carbonate of lime. They are formed by water containing carbonate of lime in solution, falling through the rocks of the cavern. The water evaporates leaving the carbonate in a solid state and little by little crystals resembling icicles are formed, hanging from the roof of the cave. Some of the water, passing down the sides of these crystals, drops to the floor, and the carbonate forms beautiful white pyramids. The crystals hanging from the ceiling are called stalactites, and those arising from the floor are known as stalagmites. The principal varieties of limestone are marble and chalk. Any limestone rock that is compact enough to allow it to be highly polish* The Banner has been granted permission to quote a series of descriptive articles from "Lessons on Common Minerals,” published bv March Brothers, Lebanon, Ohio. The book forms a valuable addition to any teacher’s library and can be had by sending the publishers thirty-five cents. ed is called marble. When composed of pure carbonate of lime, the marble is of a beautiful white color. It assumes different colors when traces of other minerals are in combination with the lime. The white marble known as saccharine or statuary marble is grained and looks like loaf sugar. It takes a fine polish and is used for building purposes and lor making statues, ornaments and tombstones. Parian marble from the island of Paros is the most valuable kind and was made famous by the ancient Grecian sculptors. It is very beautiful and durable. It was of this marble that the noted statue, the Venus de Medici, was formed. Greece produces other valuable varieties of marble. Carrara marble is chiefly used now. It is white and usually crossed by veins of a gray color. Colored marble is much used at the present time. One variety is of a green 'color, several shades of green being mingled in one specimen of marble; another kind is blood-red with white spots. There is also marble of a deep black color and a variety showing yellow and black combined. That of a gray or brown hue is in common use. Chalk is a soft variety of limestone yellowish white in color, rough to the touch and easily broken. It is too fragile to be of much service as a building material. The principal use of chalk is as a writing substance. In connection with the blackboard it is an important factor in education. It makes a distinct white mark. As has been mentioned in this article, limestone is composed chiefly of carbonate of lime. In fact, the term is only applied to a rock of which half the weight is carbonate of lime. From the carbonate, by means of heat, pure lime, a very important substance, is obtained. The limestone, chalk, or marble is heated in a kiln, and the water, carbonic acid, and other ingredients of the stone pass off in vapor while the lime sinks to the base of the kiln and is drawn out through an opening there. In this form it is known as quicklime, and is mixed with sand to make mortar. When water is poured upon quicklime, the mixture swells and steams and becomes very hot. This process is called slacking the lime. stones in buildings. It hardens and is very durable and unaffected by changes in the weather. Buildings erected centuries ago show the mortar in its original condition. Lime is a very useful article. The tanner uses it to cleanse the hides and the farmer uses it as a fertilizer. It is ako used for bleaching purposes, for refining sugar, and is an important agent in the preparation of metals and in medicine. The well-known building material called granite is composed of three minerals: quartz, felspar, and mica, the felspar being in excess of the other two metals. The rock has a grained or granular appearance, hence its name granite. It is very abundant and is distributed over all portions of the world. It is founded in great masses in mountaineous regions. Granite differs in color, the most well-known varieties being white, red, or gray. It is a beautiful compact stone, hard and durable. Although found in all parts of the world, it is more plentiful in some sections than in others. The Andes Mountains of South America and the Appalachian range of North America are rich in this rocky formation. The New England States are abundantly supplied with granite, the most valuable quarries being those of Maine. Many of the finest buildings and monuments in this country are of granite. The celebrated Bunker Hill Monument is formed of this stone. The durability of granite especially adapts it to the construction of bridges, millstones, pavements, steps, etc. This stone is obtained from quarries in Great Britain and in the United States, the principal quarries in the latter country being located in the New England States, New York, and Pennsylvania. When first taken from the quarries, slate is soft, but it hardens when exposed to the air. It is of a dark grayish color, dull and brittle, and can be split into thin layers. As a material for building purposes, slate is used for roofing houses. For this purpose the slate is cut into thin sheets of a suitable size, and these are arranged on the roof so that the sheets will lap over each other somewhat. In Continued on Third Page.
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