Foster said on unlocking the door, âperhaps youâd like me to lead the way and I can show you exactly where we found the body.â He led them into the dingy little office at the back, overturned one of the chairs, threw open a drawer in the writing table, and showed them chalk marks on the floor which indicated the position of the body. Kennedy listened attentively and moved towards the window. âYouâll be careful not to touch anything, sir,â said Foster. âWe want to leave everything just as we found it until after the inquest.â
âKeep your hair on, Inspector, Iâm not going to splash my fingerprints all over the place. By the way, I suppose youâve been over the room with a microscope looking for fingerprints? They always do that in the books.â
Inspector Foster smiled indulgently. âThat has all been attended to, sir, but you wouldnât find fingerprints on anything in this room. You see, thereâs no glossy surface anywhere.â
âWhat about the window?â
âYes, sir, there might have been a fingerprint on the glass if a man had entered by the window, but he didnât. That desk isnât smooth enough for a print and, in any case, the prints you get on furniture are very seldom of any use.â
âWhy not? I thought that if you found a fingerprint you found your man.â
Foster chuckled. âThey do that in the books, sir, but in real life you find most of the fingerprints left on furniture or glasses are blurred or smudged, without any core or any delta, and so they are useless for identification purposes.â The Scottish itch for educating had taken hold of him. âYou see, sir, what we want for identification is a rolled fingerprint like this, and a criminal does not roll his fingerprints when he touches an object.â
âNo, but when he grips a woman by the throat and strangles her, then youâve got something to work upon.â
Foster smiled with the patience practised in the kindergarten. âThe human fingers leave no impression on the flesh except a bruise. You see, sir, the impression left on a smooth surface is due to the perspiration ductsââ
âWeâll have to put you through the instruction class, Guy,â interrupted Morden. âYouâll learn a lot of things there that will put you off detective shockers for the rest of your life.â He looked at his watch. âNow we mustnât keep Mr. Foster any longer. Heâs got his work to do; and I am devilish hungry.â
Kennedyâs expression registered disappointment as he allowed himself to be piloted back through the shop. âWhat a lot of worthless junk these blighters collect. I suppose youâve turned them all over for evidence? Hallo! How the devil did that get here?â He was staring at a canvas begrimed with varnish and dirt.
âIt is clever of you to recognize it,â said Morden. âI canât even see what itâs supposed to represent.â
âNor could I until my wife gave me an art lesson. Under that black patch there thereâs a Dutch village. I had to take that on trust, and so must you. You see these blighters in the foreground: you wouldnât think it, but they are licentious Spanish soldiers come to knock hell out of the virtuous Dutchmen in the village. You see that dull red: thatâs flames from a burning house, and there in the corner you notice a lady of opulent charms with her clothes half torn off her by the licentious soldiery.â
âDoes the picture belong to you?â
âNo, it belongs to a friend of ours, Lady Turnham. By Gad! Itâs an extraordinary coincidence. I meant to speak to you about this picture this very morning, only the murder put it out of my head.â
âYou mean itâs been stolen, sir?â asked Foster, pricking up his ears.
âWell, yes, I suppose youâd call it stolen. My wife knew a lame dog in the