ON CULTIVATION OF RAPE OR COLZA FOE SEED. 375 



speedily heat, and consume the strength of the oil. The produce of an 

 excellent crop is half a French bushel, or 25 French quarts (litres), to every 

 perch of twenty-four square feet. In round numbers, the yield of the 

 crop may be estimated at twenty-five bushels to the acre — and I believe it 

 often exceeds this. The profit is so very considerable that, for some years 

 past, it is estimated that the Norman farmers pay rent and expenses from 

 the rape seed crop alone. The land rent may be averaged at one franc the 

 perch, or 70 francs the acre, which includes all taxes and rates. There is 

 another method which I would strongly recommend, and that is, to sow as 

 the Scotch farmers sow turnips. Sow in drills (manure in the drills), apply 

 guano or bone dust, or rape dust in spring, and in damp weather. 



Do not transplant at all, but thin out, and cultivate as for Swede turnip 

 seed. I believe the crop would be as heavy, and the expense diminished 

 one half, especially when labour is dear or scarce. The after-management 

 of the colza seed is not difficult, but requires attention. The seed, when 

 fresh harvested, is apt to sweat and heat. For this reason, careful farmers 

 who wish to preserve the colour and strength of the sample, generally stow 

 the seed away with a sufficient quantity of the seed-pod or husk. These 

 substances mixed through the heap, prevent its taking heat. The bulk 

 must, nevertheless, be repeatedly turned over, and the granary kept aired. 

 The yield of oil, which is the ultimate and real test of the value of the 

 crop, varies exceedingly. This variation is not so much to be attributed to 

 the variety of grain as to the nature of the soil, the geniality of the season, 

 and the care bestowed on the culture of the plant. 



If the plant be cultivated too often upon the same soil, without 

 adequate change of rotation, it will, as is often the case with clover, degene- 

 rate rapidly, and produce an inadequate return. A crop which stands well 

 and thick on the land will not always turn out to be the best oil-bearing crop. 

 I have tried the estimate in various houses, and the average is this, that it 

 requires four hectolitres, or 400 French quarts of grain, to give 200 lbs. of 

 oil in the rough. The process of rectifying the oil, facilities for purchase 

 of steam fuel, of water power, and the chemical processes connected with 

 rectification, are all elements of the expenditure. It is generally believed 

 that the English market can be more readily and cheaply supplied by pur- 

 chasing the grain in France, crushing and refining in England, than by 

 purchasing the article ready- made for use in France. 



French colza oil is constantly sold cheaper by retail in London, than its- 

 wholesale value is quoted in the Caen or Eouen colza markets. It has 

 been repeatedly asserted that English oil-crushers have purchased " rape 

 cake" in France in order to recrush it in superior machines, and then 

 dispose of the oil cake. I have heard it stated that ten per cent, on the value 

 has been gained by this species of speculation ; this is now probably at an 

 end. First, because the French crushing mills are vastly improved in 

 economy and power ; and, secondly, because the value of the rape cake is 

 so greatly increased, in consequence of the demand for it as a manure for 

 the colza crop. It appears to me that for. the fresh " virgin " soils of the 



