two o’clock
It is made from a recipe found among the papers of Rembrandt himself -- has been used with the most astonishing results on the Master 's pictures in every gallery of Holland , and is now being applied to the surface of the largest Rembrandt in Mr. P. 's own collection . Directions for use : Lay the picture flat , pour the whole contents of the bottle over it gently , so as to flood the entire surface ; leave the liquid on the surface for six hours , then wipe it off briskly with a soft cloth of as large a size as can be conveniently used . The effect will be the most wonderful removal of all dirt , and a complete and brilliant metamorphosis of the present dingy surface of the picture . '' I left this note and the bottle myself at two o'clock that day ; then went home , and confidently awaited the result . The next morning our friend from the office called , announcing himself by a burst of laughter outside the door . Mr. Green had implicitly followed the directions in the letter the moment he received it -- had allowed the `` Amsterdam Cleansing Compound '' to remain on the Rembrandt until eight o'clock in the evening -- had called for the softest linen cloth in the whole house -- and had then , with his own venerable hands , carefully wiped off the compound , and with it the whole surface of the picture ! The brown , the black , the Burgomaster , the breakfast , and the ray of yellow light , all came clean off together in considerably less than a minute of time .