The question of the sequence of application of certain methods in each case of investigating intersecting lines deserves, in our opinion, an independent consideration. This is explained by the fact that among the many methods used in the investigation of intersecting strokes, there are methods that do not have any effect on the object under study, and methods whose application leads to certain changes in the initial state of the intersecting lines, as a result of which the possibility of repeating the study Or the use of any other methods.
The first group includes microscopic and luminescent analysis of the study in various regions of the spectrum, to the second one – contact wet copying, adsorption-luminescent method, chemical processing of strokes.
When choosing methods, it is necessary, if possible, to assume that the recommended methods in each case must meet the following requirements:
• be most effective and compatible with other methods;
• It is desirable that the results of the study can be replicated by the same method and other methods;
• It is necessary to strive for a minimal change in the original appearance and states of the studied lines.
When testing various conditions for the application of methods, their effectiveness is established for various combinations of intersecting strokes, paper on which they are applied, and writing instruments. These data contribute to the solution of the problem in a specific case.
For example, GV Balashova and LP P. Savanov established that when determining the sequence of application of intersecting strokes made with black ink of equal concentration on papers of any kind with an interval of at least 5 minutes in the application time, the most effective is the method of wet copying. In the case when the intersecting strokes are made with the pastes of ballpoint pens, LN Viktorova and Ya. A. Terskaya recommend the adsorption-luminescent method.
Does this mean that if the expert will need to determine, for example; The sequence of the application of intersecting strokes made by the pastes of ballpoint pens, is it necessary to begin the investigation with an adsorption-luminescent method? Of course not. This question in all cases is solved on the basis of research using a number of methods that give the same results or, at least, do not lead to mutually exclusive results. Even the minimum degree of reliability of the applied method should be used in the process of research and the formation of an expert conclusion.
Any expert study in the technical expertise of documents, including research, whose goal is to establish a sequence of overlapping strokes, usually begins with a survey of the object under study with the naked eye and with the help of a magnifying glass and a microscope.
Microscopic examination can be used to establish very important features that indicate the order of application of intersecting strokes. It is desirable to fix them with the help of micro-shooting on black-and-white photos. Color photo materials, in our opinion, should be used to fix the color characteristics of the features (the blurring of one stroke in another, the entrainment of particles of one stroke to another, and so on).
To apply light filters at a microscopic examination of intersecting lines, it seems to us expedient to detect at the intersection of the spreads of the upper stroke in the lower or lower along the top, the drift of the particles of dyes and fibers of the paper. The choice of light filters is determined depending on the spectral characteristics of the strokes.
In a number of cases, a microscopic study of intersecting lines is useful for studying the luminescence picture in the visible, far red and infrared regions of the spectrum. We consider it necessary to note here that the methods associated with the study of luminescence can be applied in any sequence.
3. The question of the sequence of application of physicochemical and chemical methods is much more complicated. Thus, with wet copying and the adsorption-luminescent method of investigation, the section of intersection of the strokes undergoes significant changes, which completely excludes the possibility of using other methods of investigation. Irreversible changes in the object also occur when processing the intersection of strokes with micro-drops of the reagent. The use of the technique of investigating intersecting lines with pairs of concentrated nitric, hydrochloric and trichloroacetic acids, followed by restoration of strokes with 25% ammonia vapor, largely protects the document as a whole and a section with intersecting strokes from damage; The appearance of the strokes with this study is practically unchanged.
Independent findings in areas of expertise