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Show NOTES ON PAHIS QREEN. Tito Humlrril Ton ISniptnjeil In tba Unltnl Stnlrs Annuslly. l'arls green Is the most useful nnd vulunblo of the nmmleuls used iih intent in-tent Icldes. As is well knowu, Itsnetmii Is more rapid ami effective than thnlot London purple, and having u dellu'tu chemical composition it ought to bo subject to vnrlntlou In the amount of tho active agent, arsenic Its use iimiiii insecticide lias enormously extended of lnte y curs, nnd upwnid of 2.00J tons nro annually employed in the United States, besides too tons In Cnnuda. The chief dllliculty in using I'm is green N tho readiness with which It settles 1 1 tho bottom of tho tank or reservoir of tho sprnylng uppurntiiM. This Is lie-ciiuso lie-ciiuso U'Ih n rattier course powder, very much- less finely divided tliim London purple, which latter fnct gives the purple n certain ndvaiitiige. A recent conrcraut Ion with one of tl.o leading lnniuifiicturerH of Paris green has brought ont tho fact that this coarseness of grain nnd tho accompanying accompany-ing difllculty in using l'arls green in water suspension Is quite unnecessary. It seems that tho market lias hltheito demunded u very dark colored article, the lighter color having liccn deemed to ludlcnto adulteration. It seems, however, how-ever, thnt the dnrkrrcolor is simply duo to tho lnrgcr slzo of the crystals. If the green were. reduced tonn Impalpable powder, which would mnku it much mom sntisfnetory as nh insecticide, ll would lose the Intensity of Its color nnd become whitish. This inn nufactlirrr telly mo that for u number of yenrsho wnn ublo puicticully to control tho market, Isx-ause. he had discovered a means of erj stullizlng tho green lu uuusually lurgo fi.ii tides, iiecurlng n very dark-colored product, although ho wns aw nru thnt for tho uso Intended In-tended thn product so obtained wns much less rnlunble. Yet ilia darker green, with Its nccompnn-lug nccompnn-lug larger sl.ed crystals, Is moro dltll-cult dltll-cult to miiuufucturu and heiico expensive. ex-pensive. ltsccms, therefore, thn t nil theso ycnrR wo have been using n poison which could hnvo been hnd nt less expo ex-po lino and in n much moro satisfactory form. Insect Life, TREE MINES. A Curlona Imluatry of Bnuthern Ailav I.oca Ktrellenl for t'oOlna. Ono of the most curious industries In tho world Is tho business of mining for roflln planks which is enrried on In Upper Tonquln, n portion of the French possessions In southeastern Aslu. In a certulii district In this province there exists n grcnt underground deposit of logs, which we're probnbly tho trunks of trees engulfed by nn earthquake or somu other convulsion of nature nt n comparatively recent period. Tho trees, says tho Youth's Companion, Compan-ion, nro n species of pine known to the natives, and also to some extent to Hiiro Hii-ro pen n commerce, ns naiii-hoti. Tho wood is nlmost imperishable, nnd lins tho quality, cither through Its nature or as the result of its soiijourn underground, under-ground, of resisting decay from damp. This quality makes it particularly valuable val-uable for the manufacture of Collins, nnd for this purnosa it Is lnrgely ox-vnrteil ox-vnrteil to llurope, |