CRANV1P1 Indexing Procedures chapter Cyril Cleverdon Jack Mills Michael Keen Cranfield An investigation supported by a grant to Aslib by the National Science Foundation. Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government. -45 - Bakelite. But recognition of this is of little use unless the further step is taken of organizing these subclasses according to their particular relations, in terms of sub- ject content, to the class x. , i.e. , of recognizing that some are the properties of x, some are its parts, and so on. In a modern faceted classification these relationships are systematically dis- played. All terms standing in the same relation to the original class are marshalled together to constitute a category or facet of that class. So, whatever concept corn[OCRerr])rises the original class, all its Properties are assembled together, all its O})erations, all the Agents of these Operations, and so on. So far as they lend them- selves to the process, the members within each category are organized in a hierarchy and their relationship within the category is one of a thing and its kinds - kinds of properties of x, kinds of operations on x, kinds of agents of operations on x. But hierarchical l]-nkage in the strict sense, that is generic hierarchical linkage, is estab- lished between the terms within a category, not between individual terms from dif- ferent categories, or between the terms of a category and the original class. However, it is undeniable that in indexing and searching, classes are manipulated (i. e. expanded and contracted) by going outside hierarchical linkage in the strict sense defined above. The two main paths pursued are those already indicated; firstly to move from a term in one category of a class to one in another category of the s[OCRerr]ne class, e.g. Separation see also Boundary layer control (where Separation belongs to the Process facet of Boundary layer and Boundary layer control belongs to the Opera- tions facet). Secondly, to move from a term in a category to the original class giving rise to the category, e.g. Blowing see also Boundary layer (where Blowing is an operation designed to accelerate the flow in the boundary layer, and belongs to the Operations facet of Boundary layer). Both the above types of connection imply a more or less definite subject area in which the terms in question stand in some categorical or facet relation. Another type of connection is sometimes recognized, between terms which come from quite distinct areas and which are therefore not considered to have such a facet relation. The ,phase relations' of Ranganathan are one example, and some of the terms connected in syn- desis constitute another. For example, a thesaurus might link Automatic control. theory with Aerodynamic stability. Generally speaking, the view that this constitutes a quite distinct type of relation assumes a relatively arbitrary map of the field of knowledge in which subjects are assigned to one conventional class or another, such as those found in a general classification. It does not correspond to any fundamental relation between the terms which, if they have any connection at all, can be fitted into the framework of categorical or facet relations. For example, Control may be viewed as a term in an Operations facet of the subject Aerodynamic stability. It is not feasible to consider syndesis (i. e., the adjustment of classes via a system of linking references) as a device in itself since it clearly uses a mixture of several quite different relations in indicating its further classes. Neither does it seem par- ticularly profitable to make a rigid distinction between the two types of non-generic relations above since it is likely that they will overlap from time to time; e.g., Blowing may well occur in a general Control Operations facet rather than be subordinated solely to Boundary layer; in which case the linkage between Blowing and Boundary layer exemplifies the first type, not the second. Also relevant to the question of whether these relations rank as discrete devices