palmprints will frequently be found on heavy objects, since the palms as well as the fingers are employed in handling such objects. 108

A latent print is the result of perspiration exuded by the sweat pores in the ridges. This perspiration is composed of water, protein or fatty materials, and sodium chloride (salt). A latent print can be developed-- made visible--in several ways. Sometimes a latent print can be developed merely by the use of correct lighting. A second method is to brush the print very lightly with a powder, which adheres to its outline. Once a print is powdered it. can be photographed, lifted, or both. (In lifting, an adhesive substance, such as scotch tape, is placed over a powdered print. When the adhesive is lifted the powder clings to its surface. The adhesive is then mounted.) However, powder is usually effective only on objects which have a hard, smooth, nonabsorbent surface, such as glass, tile, and various types of highly polished metals and is usually not effective on absorbent materials, such as paper or unfinished wood or metal, which absorb perspiration so that there is nothing on the material's surface to which the powder can adhere. Prints on absorbent materials can sometimes be developed by iodine fumes, which may react with fatty or protein materials which have been absorbed into the object, or by a silver nitrate solution, which may react with sodium chloride which has been absorbed into the object. 109

Not every contact of a. finger or palm leaves a latent print. For example, if the surface is not susceptible to a latent print, if the finger or palm had no perspiration, or if the perspiration was mostly water and had evaporated, no print will be found. 110

Objects in the Texas School Book Depository Building

A number of objects found in the Texas School Book Depository Building following the assassination were processed for latent fingerprints by the FBI--in some cases, after they had been processed by the Dallas police. These objects included the homemade wrapping paper bag found near the southeast corner window; the C9766 rifle; three small cartons which were stacked near that window (which were marked "Box A," "Box B," and "Box C"), 111 and a fourth carton resting on the floor nearby (marked "Box D"); 112 the three 6.5- millimeter cartridge cases found near the window; and the cartridge found in the rifle. The results were as follows:

The paper bag. --The FBI developed a palmprint and a fingerprint on the paper bag by silver nitrate. These were compared with the fingerprints and palmprints of Lee Harvey Oswald taken by the Dallas police, and were found to have been made by the right palm and the left index finger of Lee Harvey Oswald. 113

The C2766 rifle. --The wood and metal of the rifle was absorbent, and not conducive to recording a good print. 114 However, the Dallas police developed by powder some faint ridge formations on the metal magazine housing in front of the trigger and also developed by powder and lifted a latent palmprint from the underside