or different colors so that an erasure on the side carrying the architectural or engineering indicia will be clearly seen in this manner drawings which are authorized by a governmental agency cannot be changed subsequent to the authorization without the agency being aware that changes have been made and without having painstakingly to compare an original drawing with a current drawing this is a major advantage of the prior invention as may be understood from the foregoing a wide variety of colors may be used pink blue green yellow or the like further the bond paper normally used in the a amp e fields has a felt side and a wire side with the felt side being smoother and on which the indicia normally is placed in the preferred embodiment of the present invention the wire side of the bond large format paper is left white for purposes of this invention white is a color as that word is used herein and the felt side of the paper is a light blue in preparing the preferred embodiment of the present invention a stock solution of direct dye obtained from the andrews paper and chemical company is made with 320 grams of direct dye per five gallons of very hot water the water can be boiling or somewhat cooler than that such as about 165 u00b0 f but the exact temperature is not critical a second dye used in the preferred embodiment of the present invention is methyl violet and a solution thereof is made from 113 grams of methyl violet dye and five gallons of hot water both of these dyes are preferably water soluble the two stock dye solutions.