224 BONES. 



It is, doubtless, exceedingly desirable that bone- 

 dust should be brought into the market free from all 

 admixture with lime ; but this will, in all probability, 

 remain an orthodox, but empty wish, inasmuch as 

 the incessant striving of competition to produce 

 cheaper and still cheaper imposes restrictions on the 

 stability and uniformity of commercial operations. 

 Under these circumstances, no other alternative re- 

 mains to the farmer, if he would be protected against 

 overcharges and imposture, than that of subjecting 

 the powder to a previous scrutiny. For this object 

 the following methods of making the examination 

 are here proposed. 



1. Test by Drying and Washing. Put the speci- 

 men to be tested into a dish, pouring over it enough 

 water to convert it into a paste, and rub it persever- 

 ingly between the fingers, whilst a further quantity 

 of water is gradually added, until the powdery parts 

 are separated from the coarser pieces. Let the 

 whole now stand undisturbed for a few seconds, and 

 then pour the superincumbent cloudy water into a 

 glass, to which water is added afresh, that, after re- 

 newed stirring and cessation, must again be poured 

 off. This washing and separation of the powdery 

 parts is to be repeated until the water is no longer 

 noticeably turbid. The residue of the bone-dust thus 

 washed off should then be spread out upon a sheet 

 of white printing-paper; a close examination of it 

 will reveal whether, and in about what quantity, 

 heterogenous substances, such as limestone, sand, 



