A VISIT TO A BONE BOILING FACTORY. 139 



articles of diet. He would cite a recent instance in connexion with C. 

 myrtifolia, in which several persons near Toulouse were poisoned by a 

 dish of snails which had been fattened on its leaves and shoots. 



b. That Royle in reference to the fruit of C Nepalensis, Peschier of 

 Geneva in regard to C. myrtifolia, and other authorities in regard to other 

 species of Coriaria, have published instances of their harmless or even 

 beneficial effects, under certain circumstances, on man or the lower 

 animals. Such conflicting statements would appear to indicate that 

 there are peculiarities in the action of the poisonous principles of all 

 the Coriarias, or discrepancies in the records of instances of the said 

 action, which discrepancies or peculiarities demand reconciliation or 

 explanation at the hands of competent scientific experts. 



A VISIT TO A BONE BOILING FACTORY. 



BY N. P. BUKGH, C.E. 



I believe that very few have any clear conception of the extent of 

 the trade in bones, home and foreign, and the various uses to which 

 they are applied, I therefore think that a brief account of a visit to the 

 factory of Messrs. L. Cowan and Sons, Hammersmith Bridge Works, 

 which I recently made in company with the Editor, may be interesting 

 to the readers of the Technologist. 



This factory, it should be observed, is on a large scale, being a com- 

 plete multum in parvo, for here are carried on the several processes of 

 soap-making, sugar refining, bone boiling, and charcoal burning, gas 

 making, and a variety of other business operations. It is with the bone 

 boiling process, &c, that I propose chiefly to deal. 



The workmen employed are so numerous that they form a rifle 

 corps in themselves, and have their own armoury, band, &c. 



We import from abroad about 65,000 tons of bones annually for 

 burning, for crushing, for manure, and for other purposes, and as 

 much, or more, is collected at home. The prime cost of these bones 

 is about three-quarters of a million sterling, while the after and sub- 

 sidiary products add largely to their value. 



The uses of the bone and its constituents are various. In order to 

 explain the processes of its conversion into a commercial article, we 

 must trace it through its several stages of manufacture. 



Arrived at the office, and having obtained the permission of one of 

 the affable and polite proprietors to inspect the works, with the assist- 

 ance ol an intelligent guide, we proceed to go over the entire range of 

 buildings. On descending to the ground floor we first see a large quan- 

 tity of bones in heaps in various places, some being in hampers, some in 



