Webster claimed to have nearly doubled the number of words given in Johnson, even after he had excluded a number which found their place in Johnson. He swelled the list, it is true, by the use of compounds under _un_ and similar prefixes, but the noticeable fact remains that he incorporated in the Dictionary a vast number of words which previously had led a private and secluded life in special word-books. His object being to make a dictionary for the American people, his ambition was to produce a book which should render all other books of its class unnecessary. Webster himself enumerates the words added in his Dictionary under five heads:-- 1. Words of common use, among which he notes: grand-jury, grand-juror, eulogist, consignee, consignor, mammoth, maltreatment, iceberg, parachute, malpractice, fracas, entailment, perfectibility, glacier, fire-warden, safety-valve, savings-bank, gaseous, lithographic, peninsular, repealable, retaliatory, dyspeptic, missionary, nervine, meteoric, mineralogical, reimbursable; to quarantine, revolutionize, retort, patent, explode, electioneer, reorganize, magnetize. 2. Participles of verbs, previously omitted, and often having an adjective value. 3. Terms of frequent occurrence in historical works, especially those derived from proper names, such as Shemitic, Augustan, Gregorian. 4. Legal terms. 5. Terms in the arts and sciences. This was then the largest storehouse, as it has since been, and the reader may be reminded that this great start in lexicography was coincident with the beginning of modern scientific research.