( G9 ) [JOG 



Jack. A term implying something common-place or ordinary, as 

 in "Jack-plane," " Screw Jack," "Roasting Jack," "Boot 

 Jack," " Jack-tax," etc. Commonly used, in the timber and 

 other trades for the hand-screw appliance that is used for 

 lifting or moving trees or timber of any kind. 



Jack-raiter. A short rafter fixed in the hips of a roof ; a piece 

 of timber in a frame cut short of its usual length often, re- 

 ceives the name of Jack. 



Jag. To notch ; to cut into notches or teeth like those of a saw. 

 In Botany, a cleft or division. 



Jain. A stoppage or congestion of logs in a stream, due to an 

 obstruction or low water. 



Jamb (Fr.). The side of a window, door, chimney, etc. 



Janker. Scotch term for a long pole on two wheels used in 

 hauling timber. 



Japanese Oak. -A class of wood uniform in grain and colour, of 

 slow growth and soft texture ; it is the produce of two 

 species, but no difference can be traced in the converted 

 wood. Its arrival on the wood-markets of Europe syn- 

 chronizes with the opening of the twentieth century, and it 

 finds favour as a companion of, or a substitute for, the 

 European wainscot-oak. It is shipped in log form, also in 

 well-converted lumber, cut radially and otherwise. See 

 other " Oaks." 



Jarrah (Eucalyptus marginata). An Australian timber of open 

 grain, durable, and one of the hardest and least inflammable 

 woods, and especially useful for paving or piles. 



Jettison. To throw cargo overboard from a vessel to lighten it 

 in a storm and prevent it foundering. 



Jib Cranes. Consist of a long jib, which can be raised or lowered, 

 and swivelled round so as to cover a considerable area. By 

 means of a rope passing over the end of the jib, loads are 

 raised or lowered either by a hand or power-driven winch. 



Jogged Timber. Squared logs irregular in their squarage, and 

 made up of different prismatic sections. 



Joggle or Stop. A method of squaring mahogany logs in sections 

 which diminish towards the top of the log. The junctions 

 are termed joggles, and each division requires separate 

 measurement. This method of manufacture is now prac- 

 tically confined to mahogany extracted in Mexico, and 

 principally to wood obtained from the Tobasco districts. 



