78 Recent Improvements in Dairy-practice. 
point out the importance of regulating the chemical condition of 
the milk when the rennet is added, and the influence which the 
state of alkalinity or acidity, under which it is coagulated, has on 
the quality and quantity of the cheese. 
In the making of butter the acetometer will be found to be of 
equal utility ; for as acidity is in some respects equivalent to an 
increase of temperature, the latter ought to be regulated by the 
degree to which the former is developed. When the cream has 
attained a high degree of acidity the temperature should be pro- 
portionally lower, and vice versa. It is because the influence of 
the chemical condition of the cream was not recognised, that no 
uniform or trustworthy results were ever obtained from experi- 
ments in churning. 
A short description of the principle and construction of this 
acetometer will suffice to render it intelligible. Simplicity and 
accuracy being the properties aimed at, a saturated solution of 
lime-water is the alkali adopted. This can be made by any 
dairymaid, and has this additional advantage, that its gravity is 
little affected by variations in the temperature ; since no calcula- 
tions or reference to tables are required, this test may be compre- 
hended and applied by any intelligent girl of twelve years of 
age. 
The instruments consist of a jar, containing a certain measure 
when full up to a given mark, and of a tube, of the same capacity, 
graduated into 100 parts. When the milk or whey is to be 
tested, the measure-glass is filled up to the mark, and the tube 
filled with the stock solution of lime-water ; as much of the latter 
is poured into the measure-glass amongst the milk, whey, or 
cream as will neutralise its acidity, as indicated by litmus-paper. 
Thus every part of lime-water poured from the tube represents 
one per cent, of acidity.* 
The introduction of this chemical instrument is among the 
earliest attempts to unite practice with science in the dairy, and 
may be regarded as marking a new era in the history of the 
manufacture of butter and cheese. 
In connexion with the improvement last noticed, a table, 
framed by the writer, for the register of observations, was lately 
introduced, and has, during the last two years, been in use in 
several dairies in the kingdom. Where this record is used, 
each cheese is impressed with characters made of wood or brass 
wire, indicating the month and day of the month corresponding 
to the entry in the table ; so that, by turning to the register, 
reference can be made at any future time to the conditions under 
* The glasses for Fulton's acetometer were made by Mr. Twaddle, price 
about 6s. 6c7. 
