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hat when the ridge detail does not show on the surface of the outer skin the underside should be examined, for many times the detail can be seen clearly. Should this be true, of course, the underside is photographed. In cases where it is noted that the outer skin is gone and the finger is not saturated with water, it is possible to dry the surface sufficiently for inking and printing purposes by rolling the finger on a blotter. If this fails, the finger is wiped off with a piece of cloth which has been saturated with alcohol, benzine or acetone, after which it may be inked and printed. _Drying the fingers_ In many instances it will be found that the outer skin is gone and the fingers themselves are saturated with water. A quick method of drying out the fingers is to place them in full strength acetone for approximately 30 minutes. The fingers are then placed in xylene for about an hour or until the xylene has overcome the reaction of the acetone. After removal from the xylene the fingers should be placed on a blotter until the surface of the fingers appears dry. They are then ready to be inked and printed. It will be noted in this procedure that when the fingers are removed from the acetone they dry and harden in a matter of seconds. The purpose of the xylene is to resoften the fingers. After this treatment, should the resulting inked impressions be unsuitable for classification purposes, the ridge detail should be photographed. _X-ray photography_ The use of X-ray photographs (radiography) has been advocated by some for purposes of recording the ridge details in decomposed, desiccated, or macerated cases. Briefly, the procedure involves the covering of the fingers with heavy salts such as bismuth or lead carbonate, in a thin, even film over the pattern area and then, by the use of the X-ray, reproducing the ridge detail. This procedure necessitates the use of X-ray equipment and a technician skilled in making radiographs. It is, therefore, an expensive operation. The results of the radiograph in no way compensate for the expense, time, and skill required inasmuch as in those cases where many wrinkles and creases appear in the fingers, especially desiccated specimens, the results have been very poor. In instances where there are no wrinkles or only a few, and where the creases are not too deep, the ridge detail is reproduced very well in the radiograph. In these cases, however, it is usually possible t
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