TUBE AND CAP IGNITION. 413 



Fill the large chamber in the plug with fine powder from a small 

 flask, inserting also a little in nipples, and screw end home. A tiny 

 key-wrench may be kept in case the latter sticks. The overcharge of 

 priming escapes through dotted channel that opens downwards in 

 screw end. When the gun is likely to be kept primed a long time 

 this orifice may be stopped with wax, else it is never necessary to do 

 so. The nipples in such case may be protected with caps flashed 

 previously in the fire ; and the gun would go off as well in a year's 

 time as the day it was loaded. The holes in safety-cover should be 

 drilled so deep that the caps are not in contact with the cover when 

 it is over them. The length of main screw depends upon substance 

 of side of barrel at breech. This screw should not go right through 

 to the inside, but leave fin. to |in. of metal between its end and 

 chamber of gun. Diameter of hole in plug, j|in. ; in screw end, Jin. ; 

 through side of barrel and in main screw, T ^in. Outside diameter of 

 plug, i in. Length of plug without ends, i^in. ; small screw end, fin. 

 long. Ends of small channels, and corresponding one through side 

 of gun, to be bushed with platina to prevent their wearing too open. 



Always try a box of caps when first opened ; if 

 they are bad, they fizz and splutter as would a damp 

 lucifer match. Don't condemn them, but subject 

 them to a great heat and they will probably be as 

 good as ever. Never risk caps or tubes becoming 

 affected by damp ; salt water is an insidious foe and 

 invades everything. Take out but a dozen or so at 

 a time from a glass bottleful kept near heat, and 

 what are not used either throw away on reaching 

 home or put in a box by themselves for further 

 proof, lest they should have suffered from damp 

 during the past day. Do not treasure caps and 

 tubes as priceless articles ; one miss-fire might lose 

 the worth of twenty boxes of them.* So be sure 



* Copper tubes were, and I may say still are, in very bad reputa- 

 tion with many fowlers. The reason of this is that gunsmiths kept 

 them in stock too long, perhaps twenty years, and then sold them as 

 wanted, which might be but in small numbers now and then. The 

 tubes made to my order by Patstone, of High Street, Southampton 

 i who. 1 may say in passing, is one of the very few gunmakers I know 

 who is an fait in all connected with wildfowl-gunning), have never 



