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investigations that have been prosecuted in this direction cannot fail to 
be of interest and value both to manufacturers and consumers. 
Nearly a year ago Dr. R. T. Brown, former chief chemist, advanced 
the idea in the annual report of this Department that the neutral or 
reverted form of phosphate of lime is as valuable for all practical pur- 
poses as the soluble or acid form, and on account of it was quite severely 
criticised by some of the agricultural chemists throughout the country. 
Now it is not our object in the present article to enter into an exhaustive 
discussion of this question, but to offer a few facts which may be of 
value to those interested in the subject. 
It was objected that although the reduced form is soluble in organic 
acids and other matters present in the soil, and in this way assimilable 
by plants, yet in the soluble form it is capable of being more completely 
mixed with the soil, and in this way brought into more thorough con- 
tact with the roots of plants, and is consequently of greater value. Bat 
when we consider that the acid phosphate, when brought into contact 
with the carbonate of lime, iron, and alumina, with a moderate degree 
of moisture, is, within twenty-four to forty-eight hours, changed into 
the neutral or reverted form, it will at once appear that, when 
applied during the dry season, as it generally is, the phosphate is 
brought into immediate contact with these constituents in the soil by 
mere mixture, and before sufficient rain falls to spread it by solution, 
the transformation, in the majority of instances, will have taken place. 
The reduction can therefore be of no greater damage before application 
than after it. Nor can storing in warehouses have the detrimental 
effects that have been ascribed to it. Indeed the recent investigations 
of Dr. Charles U. Shepard, jr., of Charleston, South Carolina, may very 
aptly be cited in support of this. He has shown by certain analyses 
that the production of reduced phosphate by storing in warehouses is 
due more to the decomposition of the insoluble phosphate than to the 
return of the acid form, since the amount of neutral phosphate formed 
in samples stored one year was in excess of the loss of the acid form. 
Preservatives—A great deal has been written during the past few 
months concerning the preservative properties of different substances, 
and among those most highly recommended are acetate and silicate 
of soda and borax. These substances, more especially the latter, have 
been spoken of as admirable preservatives of milk, and they have un- 
doubtedly a beneficial effect and cannot fail to be of practical value in 
this particular. We are rather inclined, however, to give preference to 
silicate of soda, since milk treated with a solution of “water containing 
one twenty- fifth of the silicate, will be kept perfectly sweet for five to 
six days, and if the cream be then removed the remaining fluid will be 
found to be alkaline and without a single trace of casein. Boracic acid 
is much less energetic in its action and retards the separation of cream. 
For the former, in practice, it is reeommended to dissolve about one 
ounce of the silicate in a quart of water, which may be added to about 
four gallons of milk. The fact of the addition of water may seem to 
many to be an objectionable feature in this treatment, butin many cases, 
where milk must be transported along distance to market, the discovery 
may be of great practical value not only to the producer, by supplying a 
source of income otherwise out of his reach, but also to the consumer, by 
supplying a larger quantity of a good article at reduced price. 
Ar iificial milk. —During the siege of Paris, a substitute for milk 
was manufactured according to the ‘following formula: One ounce and 
a half of sugar is dissolved in a quart of water, and to this solution are 
added one ounce of dry albumen, (from white of eggs,) and 15 to 50 
