These recommendations are good as far as they go, but in order to establish the proper standards of quality some specifications must be laid down with regard to the strength of the paper and its physical properties, together with a reference to the use for which the paper is intended. The physical condition of the paper itself apart from the nature of the fibre has much to do with its resistance to wear and tear, and this is easily proved by comparing modern book papers made from esparto with book papers of an earlier date made from the same material. The only official schedule of requirements in relation to public documents is that issued by the Stationery Office. The details set out relate chiefly to questions of weight and strength, the limits being expressed in definite form and not allowing much margin for variation in respect of strength or fibrous constituents. Mechanical wood pulp is excluded in all papers except common material as stated in the schedule. The papers required for stock are divided into twelve classes. In each class the trade names of various sized papers are given, the size of the sheet and the weight of the ream, and, where required, any special characteristics are set out. The schedule is as follows:-- _Class 1. Hand-made or Mould-made._ _General Specification._--Hand-made or mould-made. Animal tub-sized. ("Hand-made" or "Mould-made" to be marked on the wrapper.) Where special water-marking is required mould will be supplied by the Stationery Office for those papers made by hand. _Class 2. Writings, Air-dried._ _General Specification._--Plate rolled. Machine made. Animal tub-sized. Air-dried. (Must bear ink after erasure.) _Note._--The mean breaking strain and mean stretch required are given for each paper. The figures represent the mean of the results obtained for both directions of the sheet, and are calculated on a strip of paper five-eighths of an inch wide and having a free length of seven inches between the clips. _Class 3. Writings, Ordinary._ _General Specification._--Rolled. Machine-made. Animal tub-sized. _Class 4. Writings, Coloured._ _Specification._--Highly rolled. Machine-made. Animal tub-sized. _Class 5. Blotting Papers._ _Specification._--All rag. Machine-made. Free from loading. _Class 6. Printing and Lithographic Papers._ _General Specification._--Rolled. Machine-made. Engine-sized. Loading not to exceed 15 per cent. _Class 7. Coloured Printings._ _General Specification._--Rolled. Machine-made. Engine-sized. _Class 8. Copying and Tissue Papers._ _Specification._--Machine-made. Free from loading. (Copying papers are required to give three good copies.) _Class 9. Brown Papers, Air-dried._ _Specification._--Air-dried. Machine-made.