The Purchase Specifications originated with the various engineering design departments, The preparation procedure varied to suit the materials or equipment to be purchased, For the most part, Purchase Specifications for items of mechanical and electrical equipment were written by qualified personnel in the originating department and edited by the Specification Department of the Engineering Division, Other items were normally written and edited within the Specification Department, with necessary assistance furnished by the interested departments. Upon receipt of bids in the Purchasing Department, the bid papers and bid tabulations were made available to the interested engineering departments for their comments or recommendations, The Engineering Division cooperated with the Operations Division during the period between initiation of fabrication and delivery at Jobsite by passing upon the fabricator's material lists and shop drawings, and by rendering technical assistance to the Inspection and Shipping Departments of the Operations Division, A uniform system of numbering was established for Purchase Specifications and Invitations for Bids, Corresponding Specifications and Invitations had identical numbers and dates, The number consisted of three parts, separated by dates, For example, on the Specification and Invitation prepared for packaged steam generators, the number is HN-2B-401, The letters in the first element identified the documents as issued by Holmes & Narver; the number in the second element represented the use feature of the equipment or supplies, and the letter the H & N code for the site on which the equipment or supplies were to be used, the number in the third element represented by its first digit the engineering department which originated the specification and by its last two digits, the assigned serial number. This system, it may be seen, corresponded with that used for design drawings, Purchase Specifications prepared for the Project were later consolidated in Volume 3 of the General Specifications covering construc- tion work, report, These specifications are presented as Appendix "F*" of this Three hundred and six pages of Purchase Specifications were prepared, Eight pages inadvertently omitted from the collected specifications, but used, are also reproduced in Appendix "F*, Sixty-five vages prepared but not used because of changes in work required are not reproduced, BILLS OF MATERIALS In order that the Construction Department might be assisted in determining material requirements, the Engineering Division prepared Bills of Materials for design drawings. These were prepared on tracing paper so that reproducible vellums could be furnished to both the Home Office Construction Department and Jobsite. By use of these, it was possible for the Home Office Construction Department to check materiai stockpiles established by pre-design material estimates which the Engineering Division had made to expedite construction, In addition 5-19