1891.] MICROSCOPICAL JOURNAL. 225 



figure of 8. Experiments made with loo pockets similar to the one in 

 the coat confirmed these speculations with the utmost nicety. 



This fact once established, we are enabled to locate with great exact- 

 ness the position of the weapoji. A line drawn through the longer axis 

 of the figure 8 above noted, will give the position of the weapon when 

 it was discharged. 



Taking a pocket that liad been made by the tailor who made the 

 coat, and of exactly the same stuff" that was used in the original pocket, 

 after scorching it by discharging the pistol, placed hammer downward 

 (by striking the hammer with a tack-hammer through the cloth), I 

 carefully unravelled some of the threads from the scorched portion, 

 after first taking the precaution to rub the surfaces together long and 

 vigorously, and beating to remove all traces of char. I examined the 

 fibres in glycerine, first with a half-inch objective and a two-inch eye- 

 piece, and afterwai'd with a one-fifth-inch objective, to determine what 

 structural changes had been wrought in the wool fibres of which the 

 filament was composed. The first, the half-inch, instantly showed 

 that on the side exposed to heat the wool fibre had become opaque, 

 and in places considerably thickened, warped, and twisted. The area 

 and depth of the opacity were in direct ratio to the amount of heat 

 applied. The one-fifth-inch objective showed the same general fea- 

 tures, and in addition demonstrated that the opacity was due to a sort 

 of stratification or splitting up of the cortical portion, and a granulation 

 of the medullary structure of the wood. The color of originally white 

 (bleached) fibres was changed by the scorch to a reddish brown by 

 transmitted light, which was quite brown by direct light. At points 

 where the char was deep the color was dark-brown, or even black 

 throughout. Such fibres were greatly thickened, and broke easily. 

 At points where fibres were charred through, the ends were split, the 

 outer envelope curling or being retracted backward and the central por- 

 tion reduced to a granular mass. 



Cotton fibres examined in the same manner showed discoloration at 

 the point of contact with the flames, merging from coal black through 

 various gradations of brown. They were twisted and broken, and 

 where burned through the ends were black, square, or even slightly 

 concave. Much charcoal, in a minutely divided condition, was found 

 among them. This was due to the preliminary rubbing to remove the 

 completely carbonized portion. Occasionally, especiallv in charred 

 cotton batting, a whole fibre would be found completely carbonized, 

 but retaining the characteristic shape. 



After I had settled these points, 1 carefully withdi'ew from the stained 

 portion of the pocket of the overcoat, so as to leave no mark of muti- 

 lation, a few pieces of the thread, and examined them exactly as I had 

 done the foregoing, and found identically the same appearances. 



I was now in a position to swear most positively that the discolored 

 surface was a scorch made by the escaping inflamed gases from the 

 space between the cylinder and the barrel of the pistol. 



Placing the pistol in another and exactly similar pocket, hammer 

 downward, and discharging it with a tap from a tack-hammer as be- 

 fore, I carefully noted the position of the axis of the scorch and found 

 it to coincide, w^ithin a quarter of an inch, with that in the original 

 overcoat pocket. 



