634 State Board of Agriculture, &c. 



experience of everj-day life, taught liiin that a grain of sand 

 simply rubl)ed with the linger upon a piece of glass, would 

 wear the surface and produce a perceptil)le effect. Reason- 

 ing from this, he inferred that if he could l)ring a strong 

 current of sand to act in a similar manner, a proportionate 

 effect would be produced, and increasing his operations, 

 through patient labor he finally perfected tlie invention 

 now known as the sand blast. 



For this intereeting and valuable machine or appliance, 

 we are indel)ted to Prof. B. C. Tilghman, of Philadelphia, 

 who has obtained patents foi it both in America and Europe, 

 and received from the scientific world in general the 

 highest acknowledgments. 



The inventor followed up his experiments upon glass 

 with other harder substances, finding equally as practicable 

 results on sandstone, marl)le, and even flint itself, recent 

 experiments proving that it can be used for the lapidary 

 work upon gems. At some future time, perhnps, I may 

 have the liberty of presenting before your honorable Board 

 .the history and progress of the noble work which the Gov- 

 ernment has undertaken, in setting apart, embellishing and 

 adorning National Cemeteries, forthe grand army of the Un- 

 ion dead, a work unexampled and unparalleled in the history 

 of any nation, and a work tliat will forever stamp this free 

 people with tho seal of a broad, charitable, human heart. 

 It was in connection with this work, tliat the War Depart- 

 ment advertised for proposals for headstones for every 

 grave in those cemeteries containing the remains of a Union 

 soldier, whether his name was known or unknown; and the 

 contracts under which these are now being executed at 



