It may tend, perhaps, to the crystallisation of opinion on this subject if I lay down, with such precision as I can command, what must be the essential elements of any scheme likely to command success.
"In-Darkest-England-and-the-Way-Out"
Booth, William
Like the first flakes of snow whirling round and round in the mild autumn air, so words began flying in all directions in Golushkin's hot, stuffy dining-room; all kinds of words, rolling and tumbling over one another: progress, government, literature, the taxation question, the church question, the woman question; the law-court question, realism, nihilism, communism, international, clerical, liberal, capital, administration, organisation, association, and even crystallisation!
"Virgin Soil"
Ivan S. Turgenev
The terms "glassy" and "compact" feldspars only refer to structure, and not to species or composition; the student should be prepared to meet with any of the above feldspars in either of these conditions: the glassy state being apparently due to quick cooling, and the compact to conditions unfavourable to crystallisation; the so-called "compact feldspar" is also very commonly found to be an admixture of more than one feldspar species, and frequently also contains quartz and other extraneous mineral matter only to be detected by the microscope.
"The Student's Elements of Geology"
Sir Charles Lyell