398 IOWA DEPART.AIEXT OF AGRICULTURE 
The chief impurities of water may be classified as organic and inor- 
ganic. The organic impurities are either animal or vegetable substances. 
The salts of the metals are the inorganic impurities. Lime causes hardness 
of water, and occasion will be taken to speak of this when describing in- 
testinal concretions. Salts of lead, iron, and copper are also frequently 
found in water, and will be referred to hereafter. 
About the only examination of water that can be made by the average 
stock raiser is to observe its taste, color, smell, and clearness. Pure 
water is clear and is without taste or smell. 
Chemical and microscopic examination will frequently be necessary in 
order to detect the presence of certain poisons, bacteria, etc., and can, 
of course, be conducted by experts only. 
FOODS AXD FEEDING. 
In this place one can not attempt anything like a comprehensive dis- 
cussion of the subject of foods and feeding, and I must content myself 
with merely giving a few facts as to the different kinds of food, prepara- 
tion, digestibility, proper time of feeding, quality, and quantty. Improper 
feeding and watering will doubtless account for over one-half of the di- 
gestive disorders met wth in the horse, and hence the reader can not 
fail to see how very important it is to have some proper ideas concerning 
these subjects. 
KINDS OF FOOD. 
In this country horses are fed chiefly upon hay, grass, corn, fodder, 
roots, oats, corn, wheat, and rye. Many think that they could be fed on 
nothing else. Stewart, in "The Stable Book," gives the following extract 
from Loudon's Encyclopedia of Agriculture, which is of interest on this 
point: 
'In some sterile countries they (horses) are forced to subsist on dried 
fish, and even on vegetable mold; in Arabia, on milk, flesh balls, eggs, 
broth. In India horses are variously fed. The native grasses are judged 
very nutritious. Few, perhaps no, oats are grown; barley is rare, and 
not commonly given to horses. In Bengal a vetch, something like the tare, 
is used. On the western side of India a sort of pigeon pea, called 
gram (cicer arietinum), forms the ordinary food, with grass while in 
season, and hay all the year round. Indian corn or rice is seldom given. 
In the West Indies maize, guinea corn, sugar-corn tops, and sometimes 
molasses are given. In the Mahratta country salt, pepper, and other 
spices are made into balls, with flour and butter, and these are supposed 
to produce animation and to fine the coat. Broth made from sheep's 
head is sometimes given. In France, Spain, and Italy, besides the 
grasses, the leaves of limes, vines, the tops of acacia, and the seeds 
of the carob tree are given to horses. 
"For information as to the nutritive value, chemistry, and classification 
of the different kinds of food, I will refer the reader to Jordan's or 
Armsby's book on feeding animals, or to 'Smith's Veterinary Hygiene.' " 
