INSPECTION OF AGRICULTURAL LIME PRODUCTS 

 FOR THE SEASON OF 1929. 



By H. D. Haskins, Official Chemist, assisted by H. R. DeRose. 



Manufacturers and Brands. 



Twenty-nine different brands of lime and two brands of gypsum were regis- 

 tered in Massachusetts in 1929 by 21 different firms. The nature of the products 

 is shown by the following list: 



Hydrated or slaked lime 14 



Ground limestone 11 



Lime kiln ashes 2 



Precipitated lime 1 



Oyster shell lime 1 



29 

 Gypsum or land plaster 2 



The representative samples, analyses of which appear in the tables following, 

 were secured by four sampling agents who cover the state each spring when 

 drawing samjiles of fertilizer. Tlie lime samples were therefore drawn from a 

 wide area and with the same care that characterizes the sampling of fertilizers. 

 The samples should be fairly representative of the products registered, although 

 lime that has been burned and hydrated will absorb carbonic acid from the air, 

 and burned lime that has not been completely hydrated by artificial means will 

 take on moisture from the atmosphere. The amount of exposure to which such 

 limes are subjected determines the extent of changes which have occurred. If 

 the lime is in tight paper sacks, the tops of which are securely tied or fastened, 

 the changes resulting during a reasonable length of storage are not great; and 

 any change due to absorption of either water or carbonic acid does not seriously 

 diminish the effectiveness of the lime product as it simply makes the package 

 that much heavier. 



All of the lime products registered in Massachusetts during 1929 were sampled 

 and analyzed with one exception. No sample was secured of Producto Agri- 

 cultural Limestone, registered by Brewer & Co., Inc., Worcester, Mass. 



Variations and Deficiencies in the Composition of Lime Products. 



Among the hydrated, air-slaked, and precipitated limes and lime ashes re- 

 ported in Table I no serious deficiencies are found; in fact only one test out 

 of 17 brands analyzed showed a deficiency. This was in the calcium oxide found 

 in the Producto Agricultural Hydrate, sold by Brewer & Co., Inc., Worcester, 

 Mass., and in this case the 1.53 per cent calcium oxide deficiency was more than 

 made up by the overrun of 2.45 per cent magnesium oxide. A common char- 

 acteristic of all the products listed in this group is the very substantial over- 

 runs in both calcium and magnesium oxides, as compared with the minimum 

 guarantee. 



Among the ground limestones listed in Table II only one brand is noted where 

 the sum of the calcium and magnesium oxides found did not substantially meet 

 the sum of the guarantees. This was the Monarque Brand, sold by the Miller 

 Lime Products Corporation. The analysis, representing cores taken from 70 

 sacks out of 351/2 tons found at three dift'erent warehouses, shows the presence of 

 7.55 per cent insoluble matter, which might indicate that these lots were from 



