294 TO WE AS AND TANKS FOR WATER-WORKS. 



" (5) Excessively severe limitations in a specification are suici- 

 dal. They lead to constant demands for concessions, which must 

 be made if work is to be kept going, or to more or less successful 

 efforts at evasion. Better a few moderate requirements rigidly 

 enforced than a mass of excessive limitations, which are difficult 

 of enforcement, and which lead to constant friction and sometimes 

 to deception. 



" (6) There is no real reason why a specification should not 

 contain limitations derived from any source of knowledge. If 

 the limitations shown by physical test are sufficient to define 

 the necessary qualities of the material, and this test is simplest 

 and easiest made, the specification may reasonably be confined 

 to this. If a chemical analysis or a microscopic examination, 

 or a statement of the method of manufacture, or information 

 from all four, or even other sources, are found useful or valuable 

 in defining limitations, or in deciding upon the quality of material, 

 there is no legitimate reason why such information should not 

 appear in the specifications. Neither the producer nor the 

 consumer has a right to arrogate to himself the exclusive right 

 to use information from any source. 



" (7) Proprietary articles and commercial products made by 

 processes under the control of the manufacturer cannot, from 

 the nature of the case, be made the subject of specifications. 

 The very idea of a specification involves the existence of a mass 

 of common knowledge in regard to any material, which knowled<rr 

 is more or less available to both producer and consumer. If the 

 manufacturer or producer has opportunities, which are not 

 available to the consumer, of knowing how the variation of certain 

 constituents in his product will affect that product during manu- 

 facture, so also does the consumer, if he is philosophic and is a 

 student, have opportunities, not available to the producer, of know- 

 ing how the same variation of constituents in the product will 

 affect that product in service, and it is only by the two working 



