004 COLZA 



third more oil than turnips in proportion to the equal quantity of ground, and we may 

 sow it in spring or in autumn.' 



When Commerell wrote the trials were limited for want of seed ; but it now appears 

 to be well worthy the attention of agriculturists, as a plant whose rapid growth and 

 general favour, may remedy the scarcity of other crops more in use. The production 

 of the oil alone forms a considerable article of the trade of France, Belgium, England, 

 and America. 



To mining districts, to manufacturers, and others in remote localities, the valuable 

 properties of this plant and seed, as sources of oil, food, and manure, are commended. 

 Even six crops a year are said to have been taken. Thus the bitterness of famine by 

 the failure of other crops might be mitigated ; and as the oils of seeds are now 

 confusedly mixed together in commercial transactions, we have thought the useful- 

 ness of this plant should be more generally known by references to those qualities 

 recorded on its original cultivation. 



Colza oil is now extensively used for burning in lamps and for lubricating machinery. 

 The Carcel, Moderator, and other lamps are contrived to give a continuous supply of 

 oil to the wick, and by a rapid draught of air brilliant combustion of the oil is main- 

 tained without smoke. 



In the lighthouses of France and England it has been employed with satisfaction, 

 so as to replace the use of sperm-oil ; the preference has been given on the grounds 

 of greater brilliancy, a steadier flame, the wick being less charred, and the advantage 

 of economy in price. 



The Corporation of the Trinity House and the late Mr. Hume took great in- 

 terest in the question of the relative merits of colza, rape, and seed oils, as compared 

 with sperm-oil, and in 1845 referred the investigation of the power and qualities of the 

 light from this description of oil, to Professor Faraday. He reported ' that he was 

 much struck with the steadiness of the flame, burning 12 or 14 hours without being 

 touched ; ' ' taking above 100 experiments, the light came out as one and a half for 

 the seed-oil to one of the sperm ; the quantity of oil being used in the same propor- 

 tion; ' and he concludes by stating his ' confidence in the results.' 



The advantages then were, less trouble, for the lamps with sperm had to be re- 

 trimmed, and the same lamp with seed-oil gave more light, and the cost then was as 

 3s. 9d. per gallon seed-oil, against 6s. 4d. imperial gallon of sperm. 



Those interested should consult returns, ordered by the House of Commons, 

 4 LIGHTHOUSES : on the motion of Mr. Hume, " On the substitution of Sapc-seed oil for 

 Sperm-oil, and the saving accruing therefrom." \1th Feb. 1855 ; No. 75; 18th March, 

 1857, 196 and 1961.' 



In the Supplementary Returns laid before the House of Commons by the Commis- 

 sioners of the Northern Lights, there is the following report of Alan Stevenson, Esq., 

 their engineer : 



'In the last annual report on the state of the lighthouses, I directed the attention 

 of the Board to the propriety of making trial, at several stations, of the patent culza 

 or rape-seed oil, as prepared by Messrs. Briggs and Garford, of Bishopsgate Street. 

 These trials have now been made during the months of January and February, at 

 three catoptric and three dioptric lights, and the results have from time to time been 

 made known to me by the light-keepers, according to instructions issued to them, as 

 occasion seemed to require. The substantial agreement of all the reports as to the 

 qualities of the oil renders it needless to enter into any details as to the slight vary- 

 ing circumstances of each case ; and I have therefore great satisfaction in briefly 

 stating, as follows, the very favourable conclusion at which I have arrived : 



4 1. The culza oil possesses the advantage of remaining fluid at temperatures which 



thicken the spermaceti oil. 



4 2. The culza oil burns both in the Fresnel lamp and the single argand burner, with 

 a thick wick, during seventeen hours, without requiring any coaling of the wick, 

 or any adjustment of the damper ; and the flame seems to be more steady and 

 free from flickering than that from spermaceti oil. 



* 3. There seems (most probably owing to the greater steadiness of the flamo) 

 to be less breakage of glass chimneys with the culza than with the spermaceti oil.' 

 The above firm, who from thirty years' experience in the trade, were enabled to in- 

 duce the Trinity Corporation to give this oil a fair and extended trial, state that ' iVr 

 manufacturing purposes it is equally useful ; it is admitted by practical men to be the 

 best known oil for machinery ; equal to Gallipoli ; and technically it possesses more 

 " body," though perfectly free from gummy matter.' 



While sperm, Gallipoli, nut, or lard oils are rendered tiseless by the slightest ex- 

 posure to frost, the colza oil will, with ordinary care, retain its fluidity : this has been 

 acknowledged as a very important quality to railway and steam-boat companies. 

 It should be here stated that tho terms rape-oils, seed-oils, colza or culza, are all 



