PART I 



HISTORY AND CHARACTERS OF SULPHATE 

 OF AMMONIA 



THE MANUFACTURE OF AMMONIA SALTS 



The earliest forms of Ammonia with which men became 

 acquainted were, apparently, Sal Ammoniac and Spirits of 

 Hartshorn. The sal ammoniacus of Pliny, and other ancient 

 writers, appears from their account of its origin and properties 

 to have been simply rock salt. The true sal ammoniac 

 (chloride of ammonium) was certainly known to the Arabians 

 in the twelfth century, and is spoken of as imported from 

 Egypt and India. It is mentioned in the Custom-house tariff 

 of the city, of Pisa in 1408. In 1716 the Jesuit Sicard 

 describes the process for manufacturing sal ammoniac at 

 Damayer in lower Egypt. The soot obtained by burning 

 camel and cattle dung as fuel was collected, and heated in 

 closed vessels, the sal ammoniac subliming into the upper 

 cooler part as a solid cake. Sea salt and urine were, according 

 to some accounts, added to the soot. 



Small quantities of sal ammoniac occasionally occur as a 

 sublimate in the crevices of volcanoes ; this occurrence was 

 first recognised by Porta towards the end of the sixteenth 

 century. 



In Europe, during the eighteenth and early part of the 

 nineteenth centuries, ammonia was generally prepared from 



