290 CHEMICAL MANUEES. 



been a highly important source of profit to the inhabitants of the 

 Brittany coast, and has powerfully contributed to maintain a sailor's 

 nursery. As far back as 1620, in the single small village of Port 

 Louis, 4000 barrels of sardines were packed annually. Up to 1823 

 the only method of preserving sardines consisted in salting them 

 and pressing them in barrels ; they were thus put on the market 

 under the name of "pressed sardines". This method of preserva- 

 tion was replaced in 1824 by a new process kaown under the name 

 of Ampere [?Appert], its author. This process consists in removing 

 the head and the viscera from the sardines, and to pack the latter 

 in tinned iron boxes, in which they are preserved in oil after having 

 undergone a preparation known to everybody nowadays. This 

 new method produced much waste of considerable fertilizing 

 value for the soil. However, this debris was not utilized ; in the 

 beginning it was run into the sea, where it was lost without any 

 profit. It was only in 1847 that Demolon conceived the idea of 

 -utilizing it as a manure. He desired first of all to use it in the 

 raw state, but as he received it at a time when the crops had been 

 already laid down, he was obliged to store it for a certain time. 

 It then putrefied and became a pest to the neighbourhood. Demolon 

 then tried to store it by a more efficacious and less annoying pro- 

 cess. After having tried different means he conceived the idea of 

 boiling it. In that way he succeeded in extracting the oil, then he 

 dried it and reduced it into cakes which kept as well as oil cakes. 

 In 1850 he built a factory in Newfoundland to treat there the 

 debris left from the cod-fishing. The plant of this factory consisted 

 of six boilers to boil the fish, sixty presses, two graters and four mills. 

 The whole was driven by four small steam engines. The fish 

 as it came to the factory was fed into a revolving horizontal steam- 

 jacketed pan. The steam entered through the centre of this pan, 

 heated the double jacket, and in ten minutes the fish was cooked. 

 The door of the pan was then opened and the fish fell on to an 

 inclined plane. The water and oil fell into a reservoir, and the 

 solid parts were pressed, enclosed in scourtim analogous to those 

 used for the extraction of olive oil. The products were afterwards 

 dried in a stove with a superficies of 900 metres (say 3000 ft.). 

 Finally, the oil was run into a sufficient number of vats. When 

 the fish debris was boiled, pressed and grated, it was placed on 

 frames lined with cloth which pushed each other through the stove, 

 so that after half an hour the completely dried debris fell into a 

 hopper and thence into mills in which it was pulverized. 

 Without boiling the fish it could never be dried completely 

 or the oil extracted. By boiling, the oil was extracted, which 

 sufficed to pay all the costs. This manure contained 5 per 

 cent nitrogen and 49 per cent phosphate, and was sold at 30 francs 



