Historic, archived document

Do not assume content reflects current scientific knowledge, policies, or practices.

Issued January 29, 1907.

U. S. DEPARTMENT OF AGRICULTURE,

BUREAU OF ANIMAL INDUSTRY —Bulletin No. 92.

A. D. MELVIN, Chief of Bureau.

THE MILKING MACHINE AS A FACTOR IN

DAIRYING.

(A PRELIMINARY REPORT.)

I.— PRACTICAL STUDIES OF A MILKING MACHINE.

C. B. LANE, B. S., Assistant Chief, Dairy Division, Bureau of Animal Industry.

II.— BACTERIOLOGICAL STUDIES OF A MILKING MACHINE.

W. A. STOCKING, Jr., M. S. A.,

Bacteriologist , Storrs Agricultural Experiment Station., Professor of Dairy Bacteriology , Connecticut Agricultural College.

WASHINGTON: GOVERNMENT PRINTING OFFICE. 1907.

BUREAU OF ANIMAL INDUSTRY.

Chief: A. D. Melvin.

Assistant Chief: A. M. Farrington.

Chief Clerk: E. B. Jones.

Biochemic Division: Marion Dorset, chief.

Dairy Division: Ed. H. Webster, chief; C. B. Lane, assistant chief. Inspection Division: Rice P. Steddom, chief; U. G. Houck, associate chief; Morris Wooden, assistant chief. Pathological Division: John R. Mohler, chief. Quarantine Division: Richard W. Hickman, chief. Division of Zoology: Brayton H. Ransom, chief.

Experiment Station: E. C. Schroeder, superintendent; W.- E. Cotton, assistant. Animal Husbandman: George M. Rommel. Editor: James M. Pickens.

DAIRY DIVISION.

Chief: Ed. H. Webster. Assistant Chief: C. B. Lane. Assistant: Wm. Hart Dexter.

scientific staff.

Butter investigations: C. E. Gray, chemist, in charge; C. W. Fryhofer, assistant; E. A. McDonald, W. S. Smarzo, W. J. Credicott, market inspectors.

Market milk investigations: C. B. Lane, assistant chief, in charge; R. H. Shaw, chemist; George M. Whitaker, Ellis M. Santee, Ivan C. Weld, assistants.

Cheese investigations: C. F. Doane, expert, in charge. American varieties: John L. Sammis, chemist; Jay W. Moore, expert maker. European varieties: Charles Thorn, mycologist; Arthur W. Dox, chemist; T. W. Issajeff, expert maker.

Southern dairy investigations: B. H. Rawl, expert, in charge; H. N. Slater, Duncan Stuart, J. A. Conover, S. E. Barnes, J. W. Ridgway, J. E. Dorman, assistants.

Building and management investigations: B. D. White, expert, in charge; G. H. Parks, architect; W. J. Latimer, Joseph A. Lockie, assistants.

Dairy laboratories: L. A. Rogers, bacteriological chemist, in charge.

inspection staff.

Renovated butter factories: M. W. Lang, 510 Northwestern Building, Chicago, 111., in charge.

Renovated butter markets: Levi Wells, Laceyville, Pa., in charge.

Inspectors: Robert McAdam, 510 Northwestern Building, Chicago, 111.; George M. Whitaker, Washington, D. C. ; E. A. McDonald, Seattle, Wash.

Deputy inspectors: S. B. Willis, Boston, Mass.; R! A. McBride, J. H. Barrett, 6 Harrison street, New York, N. Y.; H. P. Olsen, St. Paul, Minn.

LETTER OF TRANSMITTAL.

U. S. Department of Agriculture, Bureau of Animal Industry, Washington, D. C, Oetober 13, 1906.

Sir: I have the honor to transmit herewith a preliminary report on "The Milking Machine as a Factor in Dairying," an investigation of this subject by the Dairy Division having been authorized by you. The first part deals with the practical side and the second part with the bacteriological phase of the subject.

Recent improvements in milking machines have led to their intro- duction and practical use in some of the larger dairies of the country, and there are indications that these machines may come into general use in the near future and become, an important economic factor in the dairy industry. While the investigations so far made have been too limited to justify any sweeping deductions or positive conclusions, it is believed, in view of the importance and present interest of the subject to dairymen, that the results here presented are of sufficient value to warrant their publication, and I therefore recommend the publication of this report as Bulletin No. 92 in the series of this Bureau. The investigations will be continued and further results may be reported later.

The experimental work which is the basis of this bulletin was con- ducted in August, 1905, but owing to unavoidable delays the manu- script has not been ready for publication until now.

Respectfully, > A. D. Melvin,

Chief of Bureau.

Hon. James Wilson,

Secretary of Agriculture.

CONTENTS.

I. — PRACTICAL STUDIES OF A MILKING MACHINE.

Page

Introduction 9

Some milking machines in use 10

A foot-power milker 11

A power milker 11

A milker designed for either hand or power 12

The machine used in the investigations 12

Cost of equipment for machine milking 13

Different kinds of power which may be utilized 13

Experiments in which hand and machine milking were compared 14

Experiment No. 1 14

Time required for hand and machine milking compared 17

Yield of milk from hand and machine milking compared 18

Thoroness of hand and machine milking compared 20

Experiment No. 2 20

Time required for hand and machine milking compared 24

Yield of milk from hand and machine milking compared 24

Thoroness of hand and machine milking compared 25

Quality of the milk 26

General considerations . 27

Effects of milking machines upon the cows 27

Adjusting the machines to the cows. ; . 28

Practicability of using machines for large and small herds 29

How the general introduction- of the milking machine would affect the

dairy industry 29

Suggestions for improvements 29

Objections and difficulties SO

Need for further investigations 31

Results of experience with milking machines as reported by dairymen 32

Addendum 32

II.— BACTERIOLOGICAL STUDIES OF A MILKING MACHINE.

Production of sanitary milk 33

Experiments designed to test the sanitary character of machine-drawn milk. . 34

Experiments at Farm No. 1 34

Method of experiment 34

First treatment of the milking machines 36

Second treatment of the machines 37

Third treatment of the machines 40

Fourth treatment of the machines 41

Fifth treatment of the machines 41

Sixth treatment of the machines 44

Keeping qualities of the milk 44

Summary of experiments at Farm No. 1 45

CONTENTS.

Experiments to test the sanitary character of machine-drawn milk — Cont'd. Page.

Experiments at Farm No. 2 46

Method of experiment .• 46

First treatment of the machines 47

Second treatment of the machines 48

Third treatment of the machines 49

Fourth treatment of the machines 50

Fifth treatment of the machines 52

Sixth treatment of the machines 52

Keeping qualities of the milk 54

Summary of results of bacteriological investigations 54

ILLUSTRATIONS.

PLATKS.

' ■ Page.

Plate 1. Fig. 1. A foot-power milker with attachments. Fig. 2. The same

machine in operation 12

2. Fig. 1. A power milker with attachments. Fig. 2. The same

machine in operation 12

3. Fig. 1. Milking machine for use with either hand or power. Fig. 2.

Same machine in operation 12

4. Fig. 1. Milking machine used in experiments. Fig. 2. The same

machine in operation 12

TEXT FIGURES.

Fig. 1. Bacteria in atmosphere of barn at farm No. 1 35

2. Bacteria in machine-drawn milk in experiment No. 37 39

3. Bacteria in machine-drawn milk in experiment No. 101 40

4. Bacteria in milk drawn by steam-sterilized machine in experiment

No. 101A 42

5. Bacteria in machine-drawn milk in experiment No. 103 43

6. Bacteria in atmosphere of barn at farm No. 2 46

• 7

THE MILKING MACHINE AS A FACTOR IN DAIRYING.

I.— PRACTICAL STUDIES OF A MILKING MACHINE.

By C. B. Lane, B. S. Assistant Chief, Dairy Division, Bureau of Animal Industry.

INTRODUCTION.

For more than a quarter of a century machinery has been success- fully, used in separating the cream from the milk and churning it into butter, but a machine for milking the cows has been more difficult to supply. It has long been realized that a successful and practical cow milker would mean a profitable revolution of the dairy industry, as it would render the work of milking much easier and reduce the necessity for hired help, thus making the dairyman more independent. Efforts have been made by scores of inventors for more than half a century to construct a machine that would milk cows in a satisfactory manner and without injury. The German writer Martiny states that 29 dif- ferent milking machines known to him had been patented in different countries or mentioned in the dairy literature between the years 1877 and 1898.

The annual reports of the United States Commissioner of Patents show that during the period of 34 years from 1872 to 1905, inclusive, 127 patents were taken out in this country alone for milking machines or separate parts of them. A number of machines have been success- ful in extracting the milk from the cow by either pressure or suction, or by the two combined, but have fallen short of being practical in some vital point. Naturally, inventors have attempted to imitate the way in which the calf sucks its dam. The difficulty has been to reproduce the peculiar influence which the sucking calf has upon the cow and to devise a machine which will not irritate the animal and which will do its work without injury. Another difficulty in devising a cow milker has been to construct it so that it could be adjusted to all cows. Individual animals vary greatly in the size and conformation of their udders, and even the same cow varies somewhat in the size and shape of her udder and teats during the different stages of her 11522— No. 92—07 2 9

10 THE MILKING MACHINE AS A FACTOR IN DAIRYING.

lactation period. Cows also vary greatly in disposition and temper- ament. A successful cow milker, therefore, must meet all these different conditions. Since milking must necessarily be an artificial process, it has been thought for some time that animals would become accustomed to being milked by machinery just the same as they become accustomed to hand milking, provided a milking machine could be perfected that would be comfortable to the animal when in operation. A heifer, for example, coming into milk the first time would take as readily to one artificial method as to another, other i things being equal.

While no milking machine yet invented has shown its practical value in a way that has led to its general use, recent improvements in machines of this type have resulted in greater simplicity of construction and effectiveness in operation, and consequently they are in practical use in a limited number of the larger dairies. Indeed, the prospect for the general introduction of milking machines appears to be so favor- able that it was thought advisable by the Secretary of Agriculture to authorize an investigation of the fundamental problems involved in the use of such machines. These fundamental problems may be stated as follows: (1) The practicability of substituting machine for hand • milking in the actual operations of dairying; (2) the effects of machine milking on the quantity and composition of the milk yielded by the cows; (3) the effects of machine milking on the cleanliness, sanitary character, and keeping qualities of the milk.

In making such an investigation it was, of course, necessary to select some machine for use. The machine selected is one which was found to be in actual use in a number of dairies, and one which appeared to offer adequate means for conducting the proposed inves- tigation. Its selection was not intended as in any sense a recom- mendation of this particular machine to the favor of dairynien. It is believed, however, that, in so far as the investigation has demonstrated the merits of this machine, it will benefit all inventors and manufac- turers of successful milking machines.

The authors fully appreciate the fact that these investigations have been too limited to justify any sweeping deductions or positive con- clusions. But in view of the probable general introduction of such machinery in the near future, it is believed the results of the investi- gations are of sufficient. value to justify their publication.

SOME MILKING MACHINES IN USE.

As a complete account is hereinafter given of the machine used in the investigation, a brief description will suffice for the other machines presented here, none of which were used in this investigation, and in regard to the efficiency of which no opinion can consequently be exprest.

SOME MILKING MACHINES.

A FOOT-POWER MILKER.

This machine (pi. 1) is designed for use in small herds and has no sta- tionary fixtures. It consists of a suction pump worked by foot power, 2 pieces of rubber hose, and 8 suction cups to be attached to the teats of the 2 cows, which can be milked at the same time. The milk passes thru the cylinder, and also thru the valve in the pump piston itself. The operator sits between the 2 cows and works the pump with his feet. On opening the spigot the suction rapidly draws the cups over the teats and the milk begins to flow into the milk pail, which is hung on the spout of the pump.

The teat cups are hollow and conical. Nearly an inch from the large end the cup is almost closed by a soft rubber diaphragm; this disk, being elastic, fits air-tight around the different-sized teats. The teats fill the conical cup except at the small end where suction is applied. The cup is made of three pieces of smooth hard rubber. To the end of the cup is attached a piece of glass tubing thru which the milk may be seen, and this is again connected with a small rubber tube. By means of a spigot in the tube the suction may be cut off when the teat is empty. The milk is conveyed from the spigot to the head where the milk from all four teats unites and passes into the large hose which carries it to the pail.

This machine has been in operation since 1892.

A POWER MILKER.

The accompanj'ing illustration (pi. 2) shows a cow milker which has recently been put upon the market. It consists of an ordinary milk pail made of block tin and holding about 15 quarts. On top of this pail is a tight-fitting lid of aluminum. On this lid is mounted a pump or pulsator which works automatically and causes the intermit- tent action of the machine. Connections are made by means of rubber tubing to the exhaust and air-pressure pipes, which are laid thru the stable with convenient branches between the cows. Two rubber tubes, each about 3 feet long, are also connected with convenient nozzles on the lid, and on the other end of each are 4 cups which fit snugly over the cow's teats, 2 cows being milked into one pail. As the pulsator oscillates (at the rate of about 60 times a minute) the vacuum is alter- nately turned on and off, the teat cups causing suction and release at each alternate stroke.

The machinery for operating the pulsator consists of an exhaust pump and a compressor; the exhaust produces the suction and oper- ates the pulsator . in one direction, while the compressor operates the pulsator in the opposite direction.

12 THE MILKING MACHINE AS A FACTOR IN DAIRYING.

A MILKER DESIGNED FOR EITHER HAND OR POWER.

The milking machine shown in Plate 3 consists of a simple air pump, composed of two cylinders, each of which is independent of the other in its action. One cylinder milks one cow, and one the other. The valve chambers, supported at the ends of the rods, are for the purpose of keeping the milk from running back into the pump, and also to give the pump sufficient and continued suction for the space of about ten to fifteen seconds. When the pressure is off of one of these valve chambers the milk flows from it of its own gravity into the pail. Each cow can be milked separately, or both can be milked into one pail, as desired. Cows can be milked into either open or closed pails. The machine is operated by either hand or power, the hand machine being convertible into a power machine by simply bolting an air device to it. In the operation of the power machine it is necessary to pipe the stables, a comprest air tank being required, which must be filled by some power running an air compressor. There are no pulsators or vacuum pumps in the construction of the machine. The teat cups are provided with a rubber sleeve.

THE MACHINE USED IN THE INVESTIGATION.

With this machine the milk is drawn by intermittent suction. The suction may be created by either a vacuum pump or a steam ejector. Connected with the vacuum pump is a vacuum reservoir and a pipe running the whole length of the cow stable, with a connection valve or vacuum cock between each pair of cows. A safety valve is connected to the reservoir to prevent the vacuum from running higher than is desired.

The machine itself (pi. 4, fig. 1) consists of a heavy tin pail, which is cone-shaped and holds about 55 pounds of milk. The cover of this pail is a disk, in which is a vacuum motor which produces the pulsa- tions in drawing the milk from the teats. The cover fits the pail tightly and excludes all air.

To operate the machine it is placed between the pair of cows to be milked. A rubber tube connects the pail top or pulsator with the vacuum cock above the stanchions. On opening the cock the air is drawn from the pail and the motor immediately starts. The degree of pressure' maintained is about one-half atmosphere, or 7£ pounds to the square inch. Leading from the pail cover or pulsator are two flexible tubes besides the one leading to the vacuum cock above the stanchions. At the end of each tube are 4 cups, which are fitted over the teats of the cow. The milk from the 2 cows is discharged into one pail (pi. 4, fig. 2). In operation the machine makes a low, click- ing sound, which is caused by the motor. The vacuum pulsations run from 50 to 70 per minute and may be easily adjusted to the speed

Bul. No. 92, B. A. I.

Plate 1.

Fig. 2.— The Same Machine in Operation.

Bul. No. 92, B. A. I.

Plate 2.

Fig. 2.— The Same Machine in Operation.

Buu No. 92, B A. I.

Plate 3.

Fig. 2.— The Same Machine in Operation.

BuL. No. 92, B. A. I

Plate 4.

DIFFERENT KINDS OF POWER.

required. The milk in passing from the cow to the pail goes thru a glass inspection tube, so that the operator may watch the flow. When the milk ceases to flow the suction is turned off and the action of the machine stops. Four different sizes of teat cups are provided, so that different sizes of teats may be fitted.

COST OF EQUIPMENT FOR MACHINE MILKING.

At the present time the equipment required to milk a herd of 40 cows with the machines and the cost of the same would be as follows:

1. An engine or some power with which to drive the machine. For milking up to 8 cows at a time, a 2-horsepower gasoline engine may be used.

costing $105.00

2. A vacuum pump, costing 75.00 '

3. A vacuum tank, like a tank that is used in connection with ranges or

stoves in kitchens, costing 11. 00

4. The piping with valves, etc., necessary in barn, depending upon extent

of plant, number of cows, etc., costing for a 42-cow dairy about 25. 00

5. Four milking machines, costing 300. 00

Total 516. 00

One machine milks 2 cows at a time, and it has been found practi- cable to allow one machine to every 10 or 12 cows when equipping the herd.

In a general way it may be said that the entire cost of installing a

plant for herds of different sizes would be about as follows:

For a dairy of 30 cows, with 2 machines, milking 2 cows each or 4 cows at one time, cost per cow . $13.00

For a dairy of 40 cows, with 3 machines, milking 6 cows at one time, cost per

cow 12.00

For a dairy of 60 cows, with 4 machines, milking 8 cows at one time, coat per

cow - 10. 00

For a dairy of 75 cows, with 5 machines, milking 10 cows at one time, cost per

cow 8.50

For dairy of 100 cows, with 8 machines, milking 16 cows at one time, requir- ing about a 4-horsepower engine and a larger pump, cost per cow 10. 00

One good careful man or woman can operate 4 machines milking 8 cows simultaneously, and an additional hand can not only carry away the milk, but assist in manipulating the cows' udders. The operating expense of the machines is comparatively small.

DIFFERENT KINDS OF POWER WHICH MAY BE UTILIZED.

The kind of power employed to operate cow milkers is not impor- tant provided it is uniform and can be depended upon.

Dairymen well know that, in the case of hand milking, if they were to stop for a time when a cow was partially milked and then begin again and finish milking, the chances are that there would not only be

14 THE MILKING MACHINE AS A FACTOR IN DAIRYING.

a decrease in yield, but the milk would be of poorer qualit}'. A sim- ilar effect is produced in the case of machine milking. If the engine, or whatever power is employed to work the pumps, stops for any cause during the milking, a marked decrease in the yield of milk results.

Gasoline engines. — These are most commonly employed for power at the present time.

Electric motors. — Some farmers located near cities find electricity the most convenient power. This has worked successfully on two farms at least. 'In one case a trolley line passes near the barn and a wire is attached to the main trolley wire and connected with a 1-horse- power electric motor inside of the building. As electric roads are now being rapidly built thru country districts it is quite possible that this may prove a popular method of securing power to operate cow milkers.

Steam power. — Steam engines are employed on some farms, and they will be found to work satisfactorily in supplying power to operate the milking machines. Where steam is used on farms for other purposes it can be made to run the milkers with but little extra expense.

EXPERIMENTS IN WHICH HAND AND MACHINE MILKING WERE

COMPARED.

Two experiments were conducted by the Dairy Division in which tests were made to determine the time required to milk by hand and by machine. The yield of milk, its chemical composition, and other points that were considered of interest to dairymen, were also studied.

EXPERIMENT NO. 1.

From a herd of 13 cows, 8 were selected for this test, the others being nearly dry. The animals were Jerseys and Holsteins, all 5 years old or over. This herd had been milked with the machines for over three years.

The cows were divided into two lots of 4 each in such a way that each lot gave practically the same amount of milk. The test con- tinued for thirty days and was divided into three periods of ten days each. At the beginning of the first period, Lot I was milked by hand and Lot II by machine. At the end of each period of ten days the methods of milking the two lots of cows were reversed so that the results from milking by the two methods could be compared. The milking was all performed by one man.

HAND AND MACHINE MILKING COMPARED.

Table 1. — Machine milking: Time required, to milk, and yield of milk and strappings.

Morning.	Evening.	Total for day.
	Yield of milk.	•a	Yield ol milk.		Yield of milk.
£				£
■a				3				■3			•
		8>		Z	eg	a				i
	as	CI ft	,_;	c	M	0		£		.3 'S.
a			$	0) 5		Pi	3
I		•f	o	.1	aj 0	V		3			$
H		CO	E-t	H	S3	CO	p			CO	o Eh
Min.	Us.	as.	Lbs.	Min.	£68.	1*8.	Lbs.	Min.	as.	Lbs.	Lbs.
14.00	30.50	1.25	31.75	13.00	25.00	1.60	26.50	27.00	65.50	2.75	58.25
14.00	36.50	.75	37.26	12.00	34. 75	.80	85.55	26.00	71.26	1.56	72.80
14.00	31.60	.50	32.00	13.00	28.00	a 8. 10	36.10	27.00	59.50	8.60	68.10
13.50	36.50	.76	37.25	15.00	86.50	.50	• 37.00	28.50	73.00	1.25	74.25
14.50	36.00	.50	35.50	11.50	35.00	.50	35.50	26. OC	70.00	1.00	71.00
13. 0C	36.50	.50	37.00	12.60	34.60	.50	35.00	25.50	71.00	1.00	72.00
12.50	34.00	.25	34.25	12.00	32.00	.60	32.60	24.50	66.00	.86	66.85
13.00	30.50	65.26	85.75	14.00	34.80	.40	35.20	27.00	65.80	5.65	70.95
13.00	38.00	.75	38.75	13.50	32.00	.40	32.40	26.50	70.00	1. 15	71.15
12.00	37.60	.50	38.00	12.00	29.25	.90	80.15	24.00	66.75	1.40	68.15
133.50	346.50	11.00	357.50	128.50	321.80	14.20	336.00	262.00	668 30	25 20	693.60
13. 35	34.65	1.10	35.75	12.85	32. 18	1.42	83.60	26. 20	66.88	2.52	69.85
13.00	30.00	.75	30.75	12. 50	27.30	1.80	29.10	25.50	67.80	2.55	59.85
13.50	34.50	.75	35.25	14.00	27.30	.50	27.80	27.60	61.80	1.25	63.06
13.00	34.00	.50	34.60	13.00	27.00	.50	27.50	26.00	61.00	1.00	62.00
12.50	36.00	.50	36.50	13.00	24.00	1.00	25.00	25.50	60.00	1.50	61.50
12.00	32.00	.75	32.75	13.00	24.50	.76	26.25	25.00	66.50	1.60	68.00
13.00	34.50	.76	35.25	15.00	26.25	1.00	27.25	28.00	60.75	1.75	62.50
12.50	32.50	.75	38.25	14.00	25.50	.30	26.80	26.50	68.00	1.05	59.05
13.00	33.00	.50	33.50	14.00	27.25	.75	28.00	27.00	60.26	1.25	61.50
12.50	33.50	.50	34.00	15.50	27.75	.75	28.50	28.00	61.25	1.25	62.50
18.00	34.25	.50	34.76	13.00	34.00	.40	34.40	26.00	68.25	.90	69.16
128.00	334.25	6.25	340. 60	187.00	270 86	7 75	278.60	265.00	605 10	14.00	619 10
12.80	33.42	.62	84.05	13.70	27.08	.77	27^86	26.50	60.' 51	1. 40	6l!91
11.00	36.00	.50	36.50	11.25	30.10	1.00	31.10	22.25	66.10	1.60	67.60
12.00	36.00	.25	36.25	12.00	32.00	.25	32.25	24.00	68.00	.50	68.50
13.50	33.00	.60	33. 50	15.00	^27. 75	5.25	33.00	28.50	60. 75	6. 75	66. 50
12.60	34.00	.25	34.25	13.00	<J31.00	3.76	34.75	25.50	65.00	4.00	69.00
13.00	40.00	.25	49.25	16.00	26.00	1.50	27.50	29.00	66.00	1.75	67.76
14.00	39.60	.25	39. 75	16.50	33.50	.25	33.75	30.50	73.00	.60	73.50
13.00	35.60	.60	36.00	13.50	31.00	.70	31.70	26.50	66.50	1.20	67.70
12.60	34.50	.25	34.75	14.00	36.50	.25	36.75	26.50	71.00	.60	71.60
13.60	33.00	.25	33.25	14.50	40.00	.50	40.50	28.00	73.00	.75	78.75
14.00	40.00	.50	40.50	16.00	e37.50	6.75	43.26	30.00	77.60	6.25	83.75
129.00	361.50	3.50	365.00	141.75	326.35	19. 20 344. 55	270. 76	686.85	22.70	709.50
12.90	36.15	.35	36.50	14. 17	32.63	1.92	34.45	27.07	68.68	2.27	70.96
390.50	1,042.25	20.75	1,063.00	407.25	918.00	41.151969. 15	797.75	1,960.25	61.90	2,022.10
13.02	34.74	.69	35.43	13.67	30.60	1.37	31.97	26.59	65.84	2.06	67.40

The cows and date.

LOT II, 4 COWS.

July 21

July 22

July 23

July 24

July 25

July 26

July 27

July 28

July 29

July 30

Total

Daily average

LOT I, 4 COWS.

July 31

August 1

August 2

August 3

August 4

August 6

August 7

August 8

August 9

Total

Daily average

LOT II, 4 cows.

August 10

August 11

August 12

August 13

August 14

August 15

August 16

August 17

August 18

August 19

Total

Daily average

Grand total . General average . .

a One cow held up milk (7.5 pounds) on account of stranger being in barn. &One cow held up milk (5 pounds) on account of stranger being in barn, o Black cow held up milk and gave 4.75 pounds by hand. dBlack cow held up milk and gave 3 pounds by hand (stranger in barn). « Black cow held up milk and gave 6 pounds by band.

16 THE MILKING MACHINE AS A FACTOR IN DAIRYING.

Table 2. — Hand milking: Time required to milk, and yield of milk and drippings.

The cows and date.

lot i, 4 cows.

Min

Julv21 21.00

July 22 22.00

July 23 21.50

July 21. 21.00

July 25 24.50

Jul V 20 19.50

Jlllv27 18.51

July 28 24.00

July 29 20.001

July 30 21 00|

Total......

Daily average.

lot II, 4 cows.

July 31 26.00

August 1 25. 50

August 2 21.50

August 3 23.00

August 4 23.50

August 5 21.00

August 6 24.00

August 7 22.00

August 8 23. 00

August 9 24.00

Morning.

Evening.

Yield of milk.

Lbs. 31.00 36. 00, 34. 00 32. 00' 35.00' 35. 50' 32. 00! 35. OOj 35.00, 82. 50

£5.5. 1.50 1.50 1.00 1.25 1.25 1.00 1.25 1.00 1.50 1.75

213.00 338.00 13.00 21.30 33.80 1.30

233. 50 23.35

334.00 13.25 ;.40 1.32

21.00 24. 00 21.00 21.00 21.00 20.00 21.00 21.00 20.00 20.00

28.00 31.00 28 50 3X00 33.00 32.00 30.00 31.00 31.00 32.60

21.00 30.70

1.00 .75 .60

1.25 .25 .50

1.00 . 75 .75

29.00 31.75 29.00 31.25 33.25 32. 50

Total

Daily average..

lot i, 4 cows.

August 10

August 11

August 12

August 13

August 14

August 15

August 16

August 17

August 18

August 19

Total

Daily average..

Grand total . '656. 50|979. 00 33. 75|l. 012. 75 General aver- I age 21.88 32.63 1.12 33.76

37.00 31.00 34.00 26.00 31.00 36.00 31.50 35.00 36. 50 36.00

. 75 .75 a 7. 50 .75 .75 .50 .50 .50 .50

Lbs. 32.60 37.50 85.00 33.25j 36.251 36.50 33.25! 36.00 36.50 34.25

351. 00 35.10

Min.

20.00

16.00

17.00

16. 00

20. 50

17.00

19. oo!

17.25 18.50 16.00

Yield o£ milk.

Lbs.

32.20

29. 20

28.20

3^00

29. 75

31.50

32.00

33.00

33.80

30.00

Lbs. 1.80 1.00 1.70 1.25 1.25

Lbs. 34.00 30.20 29. 90 34. 25 31.00

1.50. 36.00 1.00 33.00 1.00: 34.00 1.10 34.90 1.90 31.90

Total for day.

Yield of milk.

Min 41.000 38.000 38.500 37. 000, 45. 0001 36. 500 37. 600, 41.260 38.600; 37. 000,

Lbs 63.20 65.20 62. 20 65.00 64.75 70.00 64.00 68.00 68. 80 62.50

177.25 315.66 13. 60 329.151 17.72 31.56 1.351 32.911

390. 250 653. 65 39. 025 65. 36

37.75 31.75 34. 33.50 31.75 36.75 32.00 35.50 37.00 36.50

21.00 20. 00 19.00 21.00 20. 00 22. .50 19.00

33. 50 31.60 33. 00 31.50 33.75 32.00 31.00

23.00 30.70 21. 50 34. 20 19.00 33.40

347.25 2O6.O0324.65 34.72) 20. S0| 32.46

1.00

.50 .75 .90 1.30 1.2c .50 1.00 .76 .50

16.00, 19.00 20.00 16.00 19.00 19.00

31.00 16.00

31. 31.

33.25

18.00 17.00 18.00

25. 75

24. OO!

25. 251 28.50

26. 251 29. 00] 28. 20 29. 00 32. 001 31.601

2.00 .80 1.10 1.25 1.00 1.25

34. 50! 32. 10| 33.75 32. 40 35. 05 33.25 31. 50| 31.70' 34.95, 33.90

47.000 45.500 40.500 44. 000 43. 500 43. 500 43.000 45.000 44.500 43.000

333.10 439.500 33.31 43.950

27.75 24.80 26. 35 29. 75 27.25 30. 25

70.50 62.60 67.00 57.50 64. 76 68.00 62.50 65.70 70.70 69.40

658. 65 65.86

Lbs.

3.300

2.500

2.700

2.500

2. 250

2.000

2.600

3.660

26.500 2.650

1.750 1.250 1.500 «8.400 2. 050 2. 000 l.OOOl 1.500 1.250 1.000

21.700 2.170

1.25 33.25| 1.25 32.751

37.000 43.000 41.000 37.000 40.000 39.000! 37.0001 39.000 37. coo: 38.000|

53.75 65.00 53.75 58. 50 59. 25 61.00 58. 20 00. 00 63.00 64.00

3.000 1.550 1.6001 2.500 1.250 1.750 2.500 2.000 2.000 2.000

210. 00 307. 00 7. 50 314. 50 178. 00 279. 45 12. 65 292. 10

.75 31.45

17.80 27.94 1.26 29.21

561.26 919.75 84.60 954.35 18.71' 30.66 1.15 31.81

388.000 38.800

1,217.750 40.592

586.45 68. 64

1,898.75 63.29

20. 150 606. 600 2.015 60.660

68.3501,967. 100 2.285 65.670

a One cow held up milk (7 pounds).

HAND AND MACHINE MILKING COMPARED.

TIME REQUIRED FOR HAND AND MACHINE MILKING COMPARED.

Naturally one of the first questions asked when a dairyman is con- sidering the installation of milking machines is: How much time will be saved by their use? In the experiment outlined above one man performed the milking, 1 cow milker being used in case of the lots milked by machinery. The machine was operated by a 1-horsepower electric motor. By referring to Tables 1 and 2 the reader can readily compare from day to day the time required to milk by the two methods. A glance at the general averages for thirty days shows that the average time required for one man to milk 4 cows with the machine was 13.02 minutes in the morning and 13.57 minutes in the evening, or a total of 26.59 minutes for the day. These figures include the time used in putting the machine in place and adjusting the teat cups, about one-fourth minute per cow being required to adjust them properly.

In considering the time, the amount of milk secured should also be considered. Other things being equal, cows producing a large amount of milk require the most time to perform the milking. In case of the 4 cows milked by hand.it will be noted that it took an average of 21.88 minutes to milk them in the morning and 18.71 minutes in the evening, or a total of 40.59 minutes for the day. There was therefore a daily saving of 3.5 minutes per cow, or 14 minutes on 4 cows, thru the use of the machines.

It should be noted, however, that the time saved by the employment of machines was not the result of greater speed in milking, but in the operator's ability to milk 2 cows at once. Indeed, one man can look after 5 machines milking 10 cows at once, thus greatly increasing this saving of time. (See experiment No. 2.)

Speed of the machine. — As stated in the description, the pulsator can be adjusted so that the action will be fast or slow; 50 to 60 pulsa- tions per minute is the rate usually recommended. The more rapid the pulsations the faster the machine will milk, up to a certain limit. The writer saw one cow, giving a good flow, milked absolutely clean with a machine in 2i minutes, the number of pulsations being 150 per minute. It is believed, however, that such rapid milking for any length of time has a bad influence upon the cow and after a time she might object to the machine and refuse to give down her milk.

Cows vary greatly individually, and it is the best plan to adjust the speed of the machine as closely as possible to the requirements of each cow. Cows with short teats can be milked with the machine set at greater speed than cows with large, long teats. The ordinary type of

11522— No. 92—07 3

18 THE MILKING MACHINE AS A FACTOR IN DAIRYING.

Ayrshire cow, for example, can probably be milked by more rapid pul- sations than the Holstein. Those acquainted with milking these two types of cows by hand know this to be true, and that in milking some cows the milk is ready to be drawn as fast as the milker can manipu- late the teats.

While the machines were in operation the attendants massaged the udders of the cows and watched to see