CHAPTER XIII. 
THE METHODS OF MICROCHEMICAL QUALITATIVE 
ANALYSIS. 
In order that success may follow our efforts in the application 
of tests resulting in the production of characteristic microscopic 
crystals, it is essential that reagents be always applied in the best 
possible manner and in concentrations and under conditions such 
as will lead to the separation of a solid crystalline phase in a very 
short period of time. It is therefore necessary that we first 
ascertain the best method of procedure for each particular re¬ 
agent. Most of the failures to obtain satisfactory results when 
attempting microchemical reactions are due to a lack of apprecia¬ 
tion of the importance of this fact. Manuals of microchemical 
analysis usually neglect to state definitely the best manner of 
adding a reagent to a drop to be tested, assuming that the in¬ 
vestigator will ascertain for himself the conditions which will 
yield him products most easily identified. 
Under similar conditions as to concentration, acidity and 
manner of reagent application, the crystalline phase will not only 
almost invariably separate with the same habit, but the crystals 
will usually develop to the same size and will lie upon the object 
slide in each experiment in the same positions with respect to 
faces. 
The following methods for performing microchemical reactions 
involve different manipulations and can be considered as typical 
procedures, each applicable to the detection of a number of dif¬ 
ferent elements or compounds. The student should perform 
them until he is sufficiently proficient to invariably obtain an 
unequivocal test and one yielding each time similar crystals of a 
similar size. The more insoluble the compound, the more 
rapidly the crystals will separate and the smaller they will be. 
For convenience for future reference these methods are here 
numbered and described in detail. 
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