34 KANSAS ACADEMY OF SCIENCE. 



What is very singular in this whole proceeding is that the oxygen 

 has a very strong affection for the manganese, and consequently the 

 manganese does not give up any of its oxygen under the persuasion 

 of heat alone. It only acts as a restraining force to make the oxygen 

 leave the potassium in a quiet and orderly manner and not violently 

 and in anger, as it would be likely to do. 



We have seen how indifferently potassium lets oxygen go away 

 when it has chlorine for a companion. Let us, for an illustration, 

 observe how potassium behaves with oxygen when airthe company is 

 congenial. 



Take, for instance, potassium carbonate, which is composed of two 

 parts of potassium, one of carbon, and three of oxygen. Here the affec- 

 tion of the potassium for the oxygen is so strong that the metal potas- 

 sium must be heated until it becomes a vapor before it will consent 

 to part with the oxygen. 



If we conduct proper experiments with these apparently inert and 

 indifferent substances and observe carefully their action, we will come 

 to the conclusion that there are affectionate attachments between 

 minerals as well as between human beings and animals. 



This element, like all elements, has its individual affections. It 

 apparently does not love all alike. 



With the metals it unites in varying combinations. These combina- 

 tions are as fixed in nature's operations as our idea of the laws of the 

 Medes and Persians. 



With some metals it always divides fair, one atom of oxygen to one 

 atom of metal. It is then known as a monoxide or one oxide. 



With some metals it is a little more generous, and will put into the 

 business two atoms of oxygen to one of the metal. This firm is called 

 a dioxide, or two oxides. 



Then with some metals it is lavish in its generosity, and will put 

 in three atoms, or shares, to one of the metal ; and this partnership 

 is known as a trioxide, or three oxides. The prefixes mono, di, tri, 

 are derived from Greek words, meaning one, two, three. 



Then there are some metals with which it goes into partnership on 

 the basis of one and a half to one ; but, as there are no half atoms in 

 nature, it gets around the difficulty by putting in three atoms of oxy- 

 gen as a sesquioxide, the Latin prefix sesqui meaning one and a half. 

 This is the common combination with iron. The most abundant ores 

 of iron are sesquioxide. There are two other oxides of iron — one, the 

 monoxide, which is not of so much importance, and the magnetic ox- 

 ide, which has three atoms of iron to four atoms of oxygen. But I 

 will not afflict you with the technical properties of this element. This 

 knowledge you can secure more completely and in a more satisfactory 

 manner from chemistries and encyclopedias. 



