6S0 
Supplement to the Tropical Agriculturist." [MaRch 1, l90i 
Alcohol is made from sugar, and sugar from 
starch ; hence any fruit, vegetable, or grain con- 
taining starch (and they all do contain one or 
both of these) can be used for the manufacture of 
vinegar. The acid property of vinegar is acetic 
ncid, diluted with four or five times its bulk of 
water. Acetic ncid is not found in Nature, but is 
the result of several processes called fermentation. 
For instance, take corn meal, mix with several 
times its bulk of water, boil for a short time, 
pour into an open vessel and set it in a warm 
place and fermentation at once begins. The 
starch is converted into sugar and the product 
may be distilled or decanted off and will be what 
is known as sweet beer. This first fermentation 
is called the " saccharine fermentation," by which 
the starch ts converted into sugar : the gluten in 
the grain acts as a ferment {i.e., a yeast). Now, 
if this solution be undisturbed it will take on a 
second fermentation, called the " vinous (alcoholic) 
fermentation," whereby the sugar is converted 
into alcohol. If this compound be again let alone 
it will undergo a third fermentation, called the 
'* acetous fermentation," wliereby tlie alcohol is 
couverted into acetic acid, which, as already said, 
is the acid property of vinegar. If this ia turn be 
let alone it will undergo a fourth fermentation, 
which is called the " putrefactive fermentation," 
and is destructive. When the compound has 
reached the vinegar stage it must be decanted or 
strained off into a clean vessel and kept from con- 
tact with the air to prevent the putrefactive ferme- 
nation setting in. — N.S. W. Agricultural Gazette, 
The system of exposing to the air wine which 
it is intended to convert into viuegar is all right 
until the vinegar is obtained ; but after this it is a 
mistake to still leave the bung of the cask open 
and to still keep the vessel in a warm place. The 
Mycoderma aceti is the bacterium responsible for 
the transformation of alcohol into acetic acid, and 
by a process of oxidation of the former, for which 
air and a certain degree of heat are required, viz., 
from 86° to 90° Fahr. When the vinegar is 
strong enough, if the said conditions of exposure 
to air and heat continued to prevail, the bacteria 
referred to will decompose the acetic acid into 
water and carbonic acid, which is a further pro- 
cess of oxidation. That is why the correspondent's 
vinegar, good at first, is now a flat and nondescript 
liquid, which will very soon putrefy. Once the 
vinegar is made it should be rocked and filtered or 
clarified ; then the bung should be hermetically 
closed and the vessel stored in a cool place. 
Filling up with wine should not be omitted. This 
is done with the Tiew of preventing any access of 
air, which at this stage is no longer required and 
is even detrimental. For fixing, either kaolin or 
Spanish clay should be used, never any isinglass, 
white of egg, or gelatine, which would make the 
vinegar more turbid. Four ounces of kaolin or 
Spanish clay are enough for one fixing of a 
quantity of 20 gallons. — Ibid. 
D, E. Hutchins writing to the Cape Agriculturat 
Gazette .says : — In the Algerian Bulletin Agricole of 
the loth May, 1891, is described a sun motor which 
is in successful use at Los Angeles in California. It 
is the result of a serie? of costly experiments which 
have been in hand for some years past under some 
Boston capitalists. This machine develops a tea 
horse power. It is hoped that certain improve- 
ments will bring it up to 15 horse power. It 
works a pump which yields 62-20 hectolitres of 
water per minute. The heating power of the 
reflectors is shown by the fact that copper placed 
in the focus of the apparatus melts in a few 
seconds, and a bit of hard wood lights like a 
match, The great reflector has a diameter of 
10"55 metres, the whole surface being covered with 
1;800 glass discs. The apparatus is automatic, and 
follows the movements of the sun when onco 
started. It is hoped to utilise this machine in 
pumping water for the American railways in the 
deserts where fuel is as scarce as water. In 1889 
I saw a similar machine at work at the Paris 
Exhibition. 
The abandonment of blinker on horses is being 
advocated through the London press. Already 
their use has been discontinued to a great extent 
by Hallway and Tramway Companies and by 
carriers. 
