229 



activity, where capital, energy, and science more than compensate 

 for nature's deficiencies, and the imported citrates are turned into 

 the citric acid of commerce, which the proprietors of the vast orange 

 and lemon groves and richest sulphur deposits in the world are unable, 

 through want of capital, knowledge and enterprise to produce. 



Citrate of Lime. 



The citrate of lime which seems to be the safest form in which the 

 acid principle can be conveyed, and is the substance whence the citric 

 acid is directly manufactured, is now prepared to some extent in Italy, 

 although up to within the last quarter of a century this preliminary 

 process was considered impracticable in a remunerative point of view. 

 A very well-known authority writing in extensoonthe subject, laments 

 in forcible terms the remissness and ignorance of his countrymen in 

 Sicily, wh ; ch alone permit foreigners to reap that harvest which 

 Italians neglect to gather and garner for themselves. The objections 

 raised in bygone days, from the supposed impossibility of procuring at 

 home a sufficient quantity of proper chalk, have been shown to be 

 utterly mistaken with respect to the production of citrate of lime, 

 objections of a similar nature are now mooted with regard to the 

 production of citric acid, and have been partially disproved already by 

 the establishment of a British firm in Messina, which has undertaken 

 successfully the manufacture of citric acid in conjunction with tartaric 

 acid. 



The theory of the chemical process for compounding citrate of lime is 

 simple enough, the commercial value of the substance, however, depends 

 greatly on the purity and good quality of the chalk employed The 

 Creta Inglese, or Craie de Mendon, were until very lately considered, 

 not only the best sort of chalk for the purpose, but the only suitable 

 kind, and were exclusively used in those rare exceptional cases in which 

 citrate of lime was confectioned, rather as an experiment than as a prac- 

 tical speculation ; the exclusiveness enjoyed by English or French chalk 

 has been thought of late years, and the adaptability of Italian chalk 

 recognised very generally in the manufacture of citrate of l-me, which 

 is now undertaken successfully in many parts of Southern Italy, 

 although it is considered by some to be of a somewhat inferior quality to 

 that fabricated abroad. 



The juice which is to be operated upon is first clarified with white of 

 egg, and warmed, after which it is drawn off and filtered into tinned 

 boilers, in which it is heated to nearly boiling point and thoroughlv sa- 

 turated with finely powdered chalk, which is added gradually to the 

 liquid, this is continuously stirired until the effervesence caused bv the ad- 

 mixture of the carbonate of lime has ceased, when the deposit of citrate will 

 be approximately complete ; the remaining residue, which composes an 

 acid citrate, being also easily reducible with lime milk. The. supernatant 

 liquid is now drawn off, and the solid insoluble citrate duly compressed 

 and dried. 



Citric Acid. 



This most valuable substance, from the many and various uses to 

 which it may be applied is the concentrated acid principle of the juice 

 of the lemon, orange, and citron, but more particularly of the former, 



