Poroscopy

Poroscopy (from Greek poros-opening and scopeo-I look), a method for identifying criminals based on the openings of sweat glands on fingers. The openings of skin pores of capillary lines have certain properties that do not change in the same individual but differ among different people. Their shape is mainly oval or elliptical, but almost round or irregularly triangular forms are also encountered. The size of skin pores varies from 80 to 250 microns. Their arrangement is very variable. Sometimes they lie very densely, while at other times there are intervals of various sizes between them. Attention is also paid to the arrangement of skin pores in relation to the skin ridge. There are 9 to 18 pores per 1 cm². As an independent method for registering criminals, P. is not suitable, as it is inconvenient for classification. P. is a valuable method in cases where incomplete prints must be used, which cannot yield the desired results from dactyloscopic research. P. can also serve as a valuable supplement to dactyloscopic analysis. The study of traces must be carried out with sufficient photographic enlargements, which is a certain disadvantage of this method. The found fingerprints to be examined are photographed. Pre-coloring of them can be used; Locard recommends for this purpose lead carbonate, mercuric iodide. By establishing similarity between the found traces and the dactyloscopic pattern of the suspect, the expert can support his conclusion with data from P.