310 HISTORY AND METHODS OF THE FISHERIES. 



tbe year 1842 Caleb Cook, of Provincetown, Mass., claims to be the only person who understands 

 the art of producing this oil free from all glutinous matter and fit for use. This, he says, is done 

 by a process known only to himself not by mixing other oils or liquids with it, but by extracting 

 all the oil and gluten from it, and leaving the oil pure for the finest and most delicate machinery. 

 This, he says, cannot be done by the chilling and straining process ; for when it becomes perfectly- 

 transparent at zero, the lubricating properties are all gone, the oil runs off the pivots, spreads on 

 the plates, dries up, the pivots cut, turn red, and the oil is worse than worthless, for the valuable 

 timekeeper is no longer what it was once for the want of oil with more substance and lubricating 

 properties. 



" Porpoise-jaw oil and blackfish-melon oil are worth from $5 to $15 per gallon, according to 

 supply. These oils are sold under the above trade names, and also under the names ' watch oil' 

 and ' clock oil.' They are used largely by manufacturers of fire-arms, watches, and philosophical 

 apparatus. Smith & Wesson, of Springfield, Mass., the Ethan Allen factory at Worcester, Bye & 

 Johnson, of Worcester, the Howard Watch Company, the Elgin Watch Company, the Waltham 

 Watch Company, and the clock factories in Connecticut, use them constantly. The philosophical 

 instrument makers use them for air pumps, as they keep the leather soft and pliable. Telegraph 

 instrument makers use them when they can get them. They are used in Government light-houses 

 for the clocks of revolving lights. The color of the oils is very light, and can be made very white 

 by placing in the window, where they will bleach in a short time. One drop of water in one pint 

 of oil will injure it very much." 



