1905.] 



PUBLIC DOCUMENT — No. 33. 



107 



A study of those tables will emphasize the importance of 

 buying this class of material on a statement of a guaranteed 

 composition. Wo would urge all parties to ask for a posi- 

 tive guarantee of the amount of potassium oxide, phosphoric 

 acid and calcium oxide (although our State law does not 

 oblige the manufacturer to guarantee the latter element, it 

 should be required when buying this class of fertilizers) said 

 to be contained in this or similar classes of fertilizers. We 

 would also advise all })arties to patronize those dealers and 

 importers who have complied with our State laws by secur- 

 ing a license for the sale of their article in Massachusetts. 

 It is only in this way that protection by our State laws can 

 be secured. 



{b) Iji'me Jishe.s. — What has been said regarding wood 

 ashes applies Avith ecjual force to lime ashes. They should 

 always be bought on a statement of the guarantee of lime, 

 potash and phosphoric acid which thc}^ contain, as they are 

 more apt to vary widely in chemical composition than even 

 wood ashes. 



Table shoiving the Maximum, Minimum and Average Per Cents, of the 

 Different Ingredients found in Lime Ashes for the Seasons of 1903 

 and 1904. 



From the above comparison it will be seen that the lime 

 ashes during the present season analyzed a little higher in 

 lime and a little lower in potash than in 1903. 



3. Notes on Phosphatic Slag and Experiments with 

 Native Phosphates. 

 In one of our previous annual reports (thirteenth annual 

 report, 1901, of Hatch Experiment Station of Massachusetts 

 Agricultural College, pp. 68-70) we have discussed in detail 

 the history and timely appearance of the basic slag phosphate 



