110 ANNUAL OF SCIENTIFIC DISCOVERY. 



nearly as great. In the last case it should be remembered that the ma- 

 terial is new, possessing its full strength, and has not been subject to 

 depreciation by use. Here then, in these instances, one-half of the 

 material is needlessly destroyed at the commencement of the operation. 



The only valuable improvement recently brought out for the improve- 

 ment of paper- making, and which is designed to meet and obviate the 

 difficulty above alluded to, is embraced in a patent granted, in 1854, to 

 David A. Wells, of Massachusetts. His improvement, based upon some 

 of the simplest and most beautiful of chemical reactions, is as follows : 

 It has been found that a caustic alkali, in solution, if kept below a cer- 

 tain limit indicated by the hydrometer, is capable of dissolving and holding 

 in solution caustic lime, or other alkaline earths. 



If a certain limit of strength be exceeded, the alkaline earth is precipi- 

 tated. Remembering that potash and soda form, with gum, grease, oils, 

 coloring matters generally, and siiicia, soluble salts, and that the alkaline 

 earths form with the same substances insoluble salts, let us suppose a 

 solution of an alkali containing lime, as described, to act on a mass of 

 material, as cotton- waste, for the purpose of cleansing the same. The 

 solution being heated, the alkali attacks the grease, and becomes converted 

 into soap. In ordinary cases, the operation would here terminate. The 

 atom of alkali, joined to the atom of grease, is inert to remove and render 

 soluble any other atom of grease, and is therefore lost. But when the 

 caustic alkali has lime dissolved with it, the case is different. No sooner 

 has the alkali seized and liberated from its combination with the fibres one 

 atom of grease, than the lime, by virtue of its forming with the fat acids 

 insoluble salts, takes grease from the alkali, leaving the alkaline particle to 

 repeat its work, and again be renewed. The result is, that weak alkaline 

 solutions can thus be made to do the work of strong ones, and the expense 

 falls almost wholly on the cheap alkaline earth, leaving the dearer alkali 

 almost untouched and unimpaired. 



India as a source of materials for the manufacture of paper. At the 

 request of the English Board of Trade, Dr. J. Forbes Royle, distinguished 

 for his acquaintance with the vegetable productions of Southern Asia, has 

 published the following information respecting the fibrous materials of 

 India, which may be rendered serviceable for the manufacture of paper : 



" In reply to the reference from the Lords of the Committee of Privy 

 Council for Trade, requiring my opinion respecting increased supplies of 

 raw materials for paper making, I beg to be allowed to observe, that it is a 

 subject on which I have of late been frequently constilted, and have 

 communicated much of the following information : 



The fibrous parts of many lily and aloe-leaved plants have been converted 

 into excellent paper in India, where the fibres of tiliaceous, malvaceous, 

 and leguminous plants are employed for the same purpose as in the 

 Himalayas, one of the lace bark tribe is similarly employed, and in China 

 one of the mulberry tribe, and the iicltle in Holland. I mention these 

 various sources, t-.i'r.ni :o pi.-nit - belonging to the same families as the above 



