1. During the first 2 weeks and last 2 weeks of a 9-week period nine cows, milked by machine, were prepared for milking by hosing and washing the udders with cold water 15 min. to 1 hr. before milking, while in the intervening 5 weeks the udders only were washed with water at 115 to 120° F. immediately before milking.

2. The hot-water routine had no pronounced effect on the yield and quality of the milk from the majority of the cows, although one reacted unfavourably to a change back to the cold water routine and had to be stripped by hand.

3. The gradual restriction, over an interval of 4–6 weeks, in the milking time from 100 to 60% of the previous normal flow period for three cows in mid-lactation had no great influence on the maximum rate of milk flow from the udder, even when hot-water washing of the udder immediately before milking was introduced late in the experiment. The maximum rate of flow was, however, reached slightly sooner after putting on the teat cups.

4. The restriction in milking time caused only a small reduction in yield as the flow during the latter part of the flow period had in any case been small.

5. The fat content of the milk of the cows whose milking time was restricted fell somewhat while the solids-not-fat content remained steady.

6. Washing the udder with hot water or restricting milking time showed no clear-cut effect on the incidence of mastitis.