Chemists will hail with pleasure the announcement that a new dictionary of solubilities is in progress by a competent hand. Professor Arthur M. Comey, of Tufts College, College Hill, Mass., writes that the work he has undertaken will be as complete as possible. "The very old matter which forms so large a part of Storer's Dictionary will be referred to, and in important cases fully given. Abbreviations will be freely used and formulae will be given instead of the chemical names of substances, in the body of the book. This is found to be absolutely necessary in order to bring the work into a convenient size for use ..., The arrangement will be strictly alphabetical. References to original papers will be given in all cases ..." Professor Comey estimates his work will contain over 70,000 entries, and will make a volume of 1,500-1,700 pages. The following letter from Mr. Howard L. Prince, Librarian of the United States Patent Office, explains itself: WASHINGTON, D.C., February 11, 1891 _Dr. H Carrington Bolton._ _University Club, New York, N.Y._: DEAR SIR--In response to your request I take pleasure in giving you the following information regarding the past accomplishments and plans for the future of the Scientific Library in the matter of technological indexing. The work of indexing periodicals has been carried on in the library for some years in a somewhat desultory fashion, taking up one journal after another, the object being, apparently, more to supply clerks with work than the pursuance of any well defined plan. However, one important work has been substantially completed, viz., a general index to the whole set of the SCIENTIFIC AMERICAN and SUPPLEMENT from 1846 to date. It is unnecessary for me to point out to you the importance of this work, embracing a collection which has held the leading place in the line of general information on invention and progress, the labor of compiling which has been so formidable that no movement in that direction has been attempted by the publishers except in regard to the SUPPLEMENT only, and that very imperfectly. This index embraces now 184,600 cards, not punched, and at present stored in shallow drawers and fastened by rubber bands, and of course they are at present unavailable for use. There is little prospect of printing this index, and I have been endeavoring for some time to throw the index open to the public by punching the cards and fastening them with guard rods, but as yet have made no perceptible impression upon the authorities, although the expense of preparation would be only about $70. There has also been completed an index to the English journal _Engineering_, comprising 84,000 cards, from the beginning to date.