■ — .. M, I , ,owt imormea as a men ana hlgnly available source of nitrogen. It contains about fifteen ier cent, of nitrogen. The quantity of it on the market is comparatively small. There are many other products of the packinghouse. but these are the chief ones of interest to the fertilizer trade, and to the farmer.In the next letter I will finish describing the nitrogenous fertilizer materials, and wrfie you something about phosphates.Yours truly,JOHN M. McOANII*F»8,State C^hemlat.