Abstract: The article describes the creation and the structure of the information base covering statistical sources related to the history of Russian pipe industry in the late 19th – early 20th centuries, reviews the sources used, justifies topicality of the study and briefly characterizes pipe industry in this period. The author names four stages characterized in terms of their content and interrelation of elements, the presence of quantitative values and their analysis. The article gives examples of schemes for creating different tables that make up the basis of the resource as well as specific examples of their structure. The research novelty is the goals set and the way they are achieved. These have not been addressed by historians before as far as the industry, the chronological and territorial framework and some other parameters are concerned. Moreover, the use of mass statistical material in such a form is clearly individual and unique. In particular, the thematic digital information resource created which demonstrates operating rates of individual plants and the branch as a whole does not have analogs and can be further developed in accordance with the parameters introduced. In total, this resource consists of 25 Excel files containing 181 917 numerical values of which 73 591 are the values of sources the resource is based on. The methodology suggested for the creation of such an information base and analysis of its data can be considered a new approach to the source study of digitized mass statistical sources. 

Abstract: The article presents a source study analysis of the statistical compilation "The Iron Industry of Southern Russia" for the years 1902 - 1915, and the publication "A Collection of Statistical Information on the Mining Industry of Russia" for the years 1901 - 1911, in relation to the number of workers, their allocation in manufactories and employment occupation. The study's research subject is an in-depth study of the quantitative data concerning the workers presented in the named sources. The author examines in detail the quality and accuracy of the information regarding the number of workers in factories, their allocation in workshops, accommodation and marital status in sections of annual and monthly values. In order to determine the relative accuracy of the number and distribution of workers in manufactories, the author applied mathematical methods. In particular, the author compared the data of various Source tables with the aim of identifying possible inaccuracies and errors, with the Source tables also being subjected to cross-checking. The study's main conclusions are the identification of inaccuracies in the sources' calculations and the detection of typographical errors, the elimination of these faults and the use of corrected data which significantly improves the quality of the original historical material. Additionally, the author proves that the existing errors and inconsistencies do not adversely affect the use of the source content, and their total number and proportion is extremely small in reference to the whole volume of quantitative data, which therefore allows the author to recognize that the collections in question are reliable sources of information.