rochingcask

A wooden cistern, lined with lead, in which alum is crystallized after having been previously di olved in water or by the action of steam. roch-led-er-ite, subst. [After Herr Rochleder; suff.- ite ( Min.).] Min.: A resinous substance originally extracted by alcohol from mel an chyme (q. v.). Color, reddish-brown; transparent to translucent; melting point, 100. Composition: Carbon, 76-79; hydrogen, 906; oxygen, 14-15=100. Found also in large ma es in the lignite of Zweifelsreuth, Eger, Bohemia. rock (1), *rocke (1), *rok, *rokke (1), s. [Icel. rokkra distaff; Sw. rock; Dan. rok; O. H. Ger. roccho; M. H. Ger. rocke ; Ger. rocken. Prob. from Dan. rokke to rock (q. v.).] A distaff used in spinning; the staff or frame about which flax, wool, ., is arranged, from which the thread is drawn in spinning. rock (2), *rocke (2), *roc he, *rokke (2), subst . [O. Fr. roke , roc he , roc, from Irish & Gael. roc =a rock; Bret, roch .] IMG:content-0698.png:[blocks in formation] humorous.) 2. Figuratively : (1) A cause or source of peril or disaster (from ve els being wrecked on rocks); as, This is the rock on which he split. (2) A defense; a means of safety or protection; an asylum, a refuge. ( Scriptural .) "They remembered that God was their rock ."- Psalm Ixxviii. 35. (3) A kind of hard sweetmeat. (4) The same as ROCK-PIGEON (q. v.). "Being a bit slow in firing a fast rock escaped him." Field , April 4, 1885. II. Geol .: Any portion of the earth's crust, coherrent or incoherent, any sedimentary stratum or any dyke or overlying ma of volcanic or plutonic mineral matter. The older writers drew a distinction between rocks and soils. Both are now regarded as rocks. So are blown sand, silt, mold, and peat; though the last is soft, spongy, and of vegetable origin. Were the vegetable character to exclude it, coal would have to be omitted too. Most rocks, originally soft, have become hard and compact by losing their moisture, and being subjected to pre ure. As a rule a rock is not a bed of some simple mineral. In most cases there are crystals cemented together by imperfectly crystalline or amorphous matter, or there is a mixture of angular and rounded grains, also bound together by mineral matter. [MINERAL.] Viewed as to composition, there are three leading cla es of rock: Siliceous or Arenaceous, some formed of loose sand, others of hard sandstone, with all intermediate grades; Argillaceous rocks, i . e . rocks of clay, or more specifically having one-fourth alumina to three-fourths silica; and Calcareous rocks composed chiefly of carbonate of lime, some of them proved, and most of the others suspected, to be originally composed of various organisms. Viewed as to their origin, Lyell long recognized four kinds of rocks: Aqueous or Sedimentary, Volcanic, Metamorphic, and Plutonic (all which see). A fifth category has now been superadded, viz., Aerial or Eolian, formed by the action of wind. Aqueous, Eolian, and Metamorphic rocks are, as a rule, stratified; Volcanic and Plutonic rocks generally unstratified; the last two are called igneous. Some stratified rocks are unfo iliferous, others fo iliferous. For the stratigraphical or chronological order of the latter, see Fo iliferous. Much light has recently been thrown on the composition and origin of rocks, by subjecting thin sections of them to microscopic examination. [GEOLOGY.] Rock-cork- Mountain - cork : Rock-milk- Moun tain-milk; Rock-soap= Oropion ; Rock-oil Petro leum . On the rocks : Quite out of funds; in want of rock-alum, s. money. Min.: Sometimes applied to the ma ive form of alum. [Cf. Rock Salt.] rock-basin, s. Geol.: (1) A hollow, shaped more or le like a basin, in a rock. It may have been scooped out by a glacier; (2) A basin in a rock produced apparently by the movement of gravel, ., driven forward by water. They occur sometimes in rocks to which the sea has acce , and sometimes in granite or other rocks of mountain regions. chin, bench; go, gem; thin, this; IMG:content-0699.png:[blocks in formation] Bot.: The genus Helianthemum. rock-cod, s . A cod caught on a rocky sea-bottom. They are considered to be of better flavor than fish from a sandy bottom. rock-cook, s. Ichthy.: The small-mouthed Wra e, Labrus exo let us . It is about four inches long.