CHEMICAL SCIENCE. 251 



mal parchment, in the presence of moisture, is very prone to putrefactive 

 decomposition ; whilst parchment paper, in which nitrogen, this powerful dis- 

 turber of chemical balance, is absent, may be exposed to moisture without 

 the slightest change cither in appearance or properties. It would, in fact, be 

 difficult to find a paper-like material endowed with greater power of resist- 

 ance to the disintegrating influences of water than vegetable parchment. 



Taking into consideration the chemical composition of the new material, 

 its cohesive power, and its deportment with chemical solvents, especially 

 water, both at the common temperature, and at the temperature of its boil- 

 ing-point, it is obvious that this substance unites in itself, in a most remark- 

 able manner, the conditions of permanence and durability; and I have no 

 hesitation in stating my belief that vegetable parchment, properly prepared, 

 is capable of resisting the tooth of time for many centuries, and that under 

 various circumstances it will even last longer than animal parchment. 



The valuable properties of vegetable parchment suggest a great variety of 

 applications for the new material. 



There is no doubt that parchment paper may be adopted, with perfect 

 security, for all legal documents, policies of insurance, foreign bills of ex- 

 change, bills of lading, scrip certificates, and other similar documents, as a 

 substitute for the skins which are now genei'ally used. On the other hand, 

 its comparatively IOAV price would appear to suggest its application in a 

 variety of cases, in which, at present, paper is employed : for instance, for 

 private ledgers of banking-houses, or other large establishments, as well as 

 for registries of wills, marriages, baptisms, and deaths. Even for the manu- 

 facture of bank-notes it may be found useful; indeed, for all documents, the 

 preservation of which is of importance. Many of the documents in question, 

 in order to protect them from injury in case of fire, are generally kept in safes, 

 the majority of which are now encased with solid water the water of crys- 

 tallization in alum, and other similar hydrated compounds. The interior of 

 these safes, in case of exposure to heat, must, obviously, become filled with 

 steam of a high temperature, and it cannot be doubted that documents writ- 

 ten on vegetable parchment, owing to the extraordinary power with which 

 this material resists the action of boiling water and of steam, will stand a 

 much better chance of preservation under such circumstances, than those 

 written on common paper or animal parchment. 



As another advantage of vegetable parchment as compared with animal 

 parchment, the experience may be quoted, that vegetable textures are much 

 less attractive to insects than animal structures. Moreover, to increase the 

 security of vegetable parchment in this respect, the paper, before conversion, 

 may be incorporated with chemical agents, which, like salt of mercury, for 

 instance, have been employed with such advantage in the manufacture of 

 paper for public records. 



In considering the applicability of vegetable parchment for legal docu- 

 ments, another property of this remarkable material, although perhaps of 

 minor importance, deserves nevertheless to be noticed. This is the great dif- 

 ficulty with which words are erased from its surface, and others are substi- 

 tuted in their places. Deeds written on parchment paper acquire thereby a 

 certain degree of security against falsification. 



Its strength and resistance to water appear to recommend parchment paper 

 in an eminent degree for engineers' and architects' plans, and especially for 

 their working plans, which are often unavoidably subjected to rough usage 

 and moisture. The thinner sheets of parchment paper, on account of their 



