Tlio Industrial Monthly thus treats of 10 baso of what we xisually term sand. Ve do not, howevor, indorse tho infallilüily ot tho applications mcntiouud, to 'ruit treos and vinos, although thero 18 vidence in the direotíon statcd by our ontemporary : Silica gives harshncss and stiffness to le straw and leaves of cereal ajrain. Vhen whcat or rya is sown where a brush íeap or pilo ot los has been burned to shos, tho straw will be uinisnally stiff, lid tho leavos much harsher than othcr :raw whicli grow iu close proxiraity to :io place wliore til1 ashos of tho wood or jrush wero left to fertilizo the soil. Tho b of the ashe3 and the silica found i t he soil aro taken up by the growing lants, and form a coating of liquid glass, vhich s spread ovenly over the straw nd leaves of tho growiug grain, as a raeallic coat of arms was used in oldon irnos to cover tho body of the soldier. Vhen the growing straw of whoat is enlosedin a thin tube of elastic glass, tho nnumerable spores which frequently fill lio ontiro atniosphere like flakes of snow, lid which produce rust, do not find a Ongeuial place for thoir lodgment and omplcte dovelopinont. But when the pl: nts do not havo access to a genorous iupply of silica and potash, the sterns aro o limber thut they are onsily prostratod )y driving storms, so that the oars ot ] grain will bo doveloped only in part. ] Vhen tho silica is availablo only in small ( [iiantities, tlie spores from which the . ;i spring adbere to tbe loavee and sterns, , vhere they find a congenial place for ,heir developinent, and thus tho produe ivenoss of the planta ík soriously impaired. The practical value of silica is further icrceived in tho production of excellent 'ruit. lf tbe kou noar au apple or poar ;ree that luis hitherto yielded knotty and rusty fruit recoives a liberal dressing of saiiil, whioh Buppliea silica, and of wood ashes, which furnishes potash, - the subBtances required to make glass - nature would eniploy theso ingrediente to a jreat extent in oovering the loavcs with in elastic glass, and tbe fruit with a thick bransparent vamiah, produeeJ. from the lilioa miei potash, which will protect llio Leavesfroin blight, and the fruit from rust, soulos and oracks. The fact has ropoatedly beon demonstratedin some fruitproduoing localities, whcre wood ashes or coal ishos have been tcattered around about pear trees und ajijilos trees so liberally that all grass and woeds wero destroyed. Flint, sharp sand, and quartz are oomposed for the most part of silica. Henee tho propripty of mixing soouring-aand with the soil in which flowers are cultivated. Divest the soil of all silica and ilknli wbeie usoful plants and beautiful flowera are to be grown, and not one will attain to perfect development, simply because silica and potnsh aro emincntly esBential to impart stiffness to th sterns, and elastioity and tena city to tho leaves. When grape vines, for example, which ara growing in a sandy soil, have accoss to potnsh in abundancc, the leaves will appear M tough as leather, and no mildew or rust will ever affect the foliage, or injure the fruit. Tu the philosophic world, silica and alkal ino earths havo given us the microscopio and telescopio lonses, which havr untoldcd to our linutcd visión the matchless wonders of the planetary universo ancl the tl anscendont beauties of insect Ufe, whicli can newrbeappreciated when i viowod with the naked oye.