TESTING THE BURNING QUALITY OF TOBACCO. 37 



by the character of the wrapper and binder. Furthermore, this lack 

 of cohesion in the ash of a wrapper may be largel}^ overcome by the 

 use of a good binder. As to the color of the ash, a binder having a 

 good burn will impart to the ash of the wrapper a lighter tint and a 

 more uniform color. The general results of these experiments may 

 be summarized as follows: 



(1) In order to secure a good burn, due consideration should be given 

 to the proper balancing of the components of the cigar; that is, aheav}" 

 filler should be wrapped with a comparatively heavj^ wrapper, while a 

 light-bodied filler requires a light-bodied wrapper. 



(2) . Of the three components of the cigar, the filler exerts the strongest 

 influence on the evenness of the burn. 



(3) The influence of the wrapper and binder is shown most strongly 

 on the character of the ash, and the binder very materialh" influences 

 the ash of the wrapper in this respect. 



TESTING THE CAPACITY FOR HOLDING FIRE AND THE 

 EVENNESS OF THE BURN. 



The factors of holding fire and of burning evenly are of prime 

 importance in judging the burn of tobacco, and any sample found 

 markedly deficient in these points may be rejected without applying 

 any further test. As has been previously stated, the old method of 

 measuring the fire-holding capacity is likeh^ to lead to erroneous con- 

 clusions, while there has heretofore been no direct method of deter- 

 mining the evenness of the burn of wrapper leaf. In the process 

 which we have used for testing wrapper tobacco with regard to these 

 elements of the burn, the area of the leaf consumed, rather than the 

 time elapsing before the glow is extinguished, is measured. 



The form of the apparatus used in this method will be understood 

 by reference to the accompanying illustration (fig. 3). The essential 

 feature is the form on which the leaf is wrapped, consisting of a col- 

 lapsible wooden tube, one end of which fits into a glass tube of the 

 same diameter. This latter is in turn connected with a second glass 

 tube through which is drawn a current of air. The best material for 

 making the wooden form is well- seasoned cherr}^ with a straight grain, 

 but ash has also been found to answer the purpose very well. From the 

 wood selected is made a cylinder 5 inches in length, f inch in diameter 

 at one end, and tapering slighth^ to the other end (see fig. 4). In the 

 larger end of the cylinder a f -inch hole is bored to a depth of 3f inches, 

 and the shell thus formed is separated into six equal segments by saw- 

 ing to a depth of 3i inches. The smaller end is cut down for a dis- 

 tance of li inches, so as to fit snugly into the glass tube. The shoulder 

 thus formed should correspond in depth to the thickness of the wall of 

 the glass tube. Near the larger end of the form a groove (c) is cut, 

 into which is fitted a rubber band. The plug {d) has a diameter such 



100— IV 



