. Bulletin - New York State Museum. Science. GUIDE TO THE MIXERALOGIC COLLECTIONS 5 called quartz; a white, pink or salmon colored mineral which shows on the fracture a series of smooth surfaces and which is called a feldspar; and a black fibrous mineral which is known as hornblende. Crystallization When a substance in the condition of a liquid or a gas becomes solid it is often seen that this solid has a regular outline, smooth, bright sides or faces and sharp angles. This results from the fact that the particles or molecules of the substance, which while it was liquid or gaseous rolled about
. Bulletin - New York State Museum. Science. GUIDE TO THE MIXERALOGIC COLLECTIONS 5 called quartz; a white, pink or salmon colored mineral which shows on the fracture a series of smooth surfaces and which is called a feldspar; and a black fibrous mineral which is known as hornblende. Crystallization When a substance in the condition of a liquid or a gas becomes solid it is often seen that this solid has a regular outline, smooth, bright sides or faces and sharp angles. This results from the fact that the particles or molecules of the substance, which while it was liquid or gaseous rolled about on one another, have been in some way arranged, grouped and built up. To illus- trate this, suppose a quantity of small shot to be poured into a glass, the shot will represent the molecules of a substance in. Fig. 1 Fig. 2 Fig. 3 the liquid state, as for example a solution of alum. If, now, we suppose these same shot to be coated with varnish or glue so that they will adhere to each other and imagine them grouped as shown in fig. 1 they will represent the arrangement of the mole- cules of the alum after it has become solid or crystallized. This arranging, grouping and piling up of the molecules is called crystallization and the solid formed iu this way is called a crys- tal. Fig. 2 and 'A show the shot arranged to reproduce two com- mon forms of crystals. There are many common examples of crystallization. The snowflakes, which are formed by the cooling of watery vapor in the air. are composed of small crystals which are quite apparent to the eye and are often of great beauty and regularity of form. The same may be said of the frost which forms on a window. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original New York State Museum; New York State Museum. Albany : New York State Education Dept
Size: 2776px × 900px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectscience, bookyear1887
