The otto is put up in squat-shaped flasks of tinned copper, called _kunkumas_, holding from 1 to 10 lb., and sewn up in white woolen cloths. Usually their contents are transferred at Constantinople into small gilded bottles of German manufacture for export. The Bulgarian otto harvest, during the five years 1867-71, was reckoned to average somewhat below 400,000 _meticals, miskals_, or _midkals_ (of about 3 dwt. troy), or 4,226 lb. av.; that of 1873, which was good, was estimated at 500,000, value about £700,000. The harvest of 1880 realized more than £1,000,000, though the roses themselves were not so valuable as in 1876. About 300,000 _meticals_ of otto, valued at £932,077, were exported in 1876 from Philippopolis, chiefly to France, Australia, America, and Germany. --_Jour. Soc. of Arts._ * * * * * A NEW METHOD OF PREPARING METATOLUIDINE. By OSKAR WIDMAN. The author adds in small portions five parts metanitro-benzaldehyd to nine parts of phosphorus pentachloride, avoiding a great rise of temperature. When the reaction is over, the whole is poured into excess of cold water, quickly washed a few times with cold water, and dissolved in alcohol. After the first crystallization the compound melts at 65°, and is perfectly pure. * * * * * A catalogue, containing brief notices of many important scientific papers heretofore published in the SUPPLEMENT, may be had gratis at this office. * * * * * THE SCIENTIFIC AMERICAN SUPPLEMENT. PUBLISHED WEEKLY. TERMS OF SUBSCRIPTION, $5 A YEAR. Sent by mail, postage prepaid, to subscribers in any part of the United States or Canada. Six dollars a year, sent, prepaid, to any foreign country. All the back numbers of THE SUPPLEMENT, from the commencement, January 1, 1876, can be had. Price, 10 cents each. All the back volumes of THE SUPPLEMENT can likewise be supplied. Two volumes are issued yearly. Price of each volume, $2.50, stitched in paper, or $3.50, bound in stiff covers. COMBINED RATES--One copy of SCIENTIFIC AMERICAN and one copy of SCIENTIFIC AMERICAN SUPPLEMENT, one year, postpaid, $7.00. A liberal discount to booksellers, news agents, and canvassers. MUNN & CO., PUBLISHERS, 37 PARK ROW, NEW YORK, N. Y. * * * * * PATENTS. In connection with the SCIENTIFIC AMERICAN, Messrs. MUNN & Co. are Solicitors of American and Foreign Patents, have had 35 years' experience, and now have the largest establishment in the world. Patents are obtained on the best terms. A special notice is made in the SCIENTIFIC AMERICAN of all Inventions patented through this Agency, with the name and residence of the Patentee. By the immense circulation thus given, public attention is directed to the merits of the new patent, and sales or introduction often easily effected.