ing a few small machines scattered around. In No. 5 factory the greater part of the machinery was on the fourth and fifth floors, requiring six belt transmissions to reach the machinery from the engine with a few small machines scattered on the first, second and third floors.

In No. 4 factory the arrangement of the machinery was similar to No. 5.

From these tests it appears that when machinery can be arranged so that the transmission is through one line of shafting from the engine to the machine, the efficiency obtained will compare favorably with any other method of power transmission.

When the machinery cannot be so conveniently arranged, and when it will be necessary to transmit the power from the engine o the machines through three or more lines of shafting, the efficiency of a belt transmission falls so low that some other method will be more economical.

Mr. Clark: I would ask Mr. Westover if he made any comparison on the efficiency of the system after he put in electric motors and betore he put in electric motors on the shafting? He said they were replaced by electric motors and he checked up the readings on the engines for its useful load. Can he give us any comparison of the efficiency obtained by that test?

Mr. Westover: I cannot give any comparisons; I made no test after the electrical installation was made. That has only recently been made and the tests of those I suppose will be made within some two weeks, when we can get a comparison between the two.

Mr. Robt. R. Arbell next presented views of rope transmission in use in various shops in Chicago, describing each in its turn. This subject was fully described and illustrated in No. 3, Vol. II., 1897, of the Journal of this society.

The President: The subject is open for general discussion. Is there any member that has anything to offer on the subject?

Mr. T. T. Johnston: It seems to me that this subject is much too bewildering for me to talk intelligently upon. We find in one place compressed air driving a generator and in another place a generator driving an air compressor; in one place we have a rope drive driving a pump and in another place we have a pump driving a rope drive, and so on, and it makes the subject too complicated.

I have very little to say on the subject excepting perhaps in regard to one thing that has been touched upon, and that is with regard to transmission of power by water. It is very frequently done, and the particular thought that was floating in my mind is the great advances that have been made in the design and manufacture of water motors, especially pressure wheels under very high heads. There has been constructed very recently by an

American concern a turbine wheel to operate under a head of 260 feet; I have seen a design of one to operate under 260 feet to generate 3,800 horse power, and the whole machine could be put in one end of this room very comfortably, the result of which has been to enable large units to be generated under quite high heads, something that has hitherto been out of the question. I think perhaps if the Niagara people had their work to do over again to-day, they would do it differently from what they have done, on account of the great strides that have been made in making water motors, and other appliances.

A Member: I would like to ask if any one here is able to state whether there has been any application of electricity to the modern flouring mill and with what success?

Prof. Jackson: There are many flouring mills driven by electric motors. The motors in some cases are driven from central stations in which steam engines are the prime movers, and in other cases they are driven from central stations in which water wheels are the prime movers.

A Member: May I expand that question to the extent of asking, are there any of the large mills, that is, those who are operating and turning out thousands of barrels a day, that are driving their machinery by electricity?

Prof. Jackson: There are a number of large mills, but I cannot give their capacities. Success in electric driving in this case is not a question of capacity of the mill; it is a question of the steadiness of the power. Satisfactory results have been obtained in various mills that have been equipped in regard to steadiness of power; and the extension to larger mills is purely a question of using more or larger motors.

A Member: Do you know if the power is applied directly to the roller itself or to the general shafting of the mill?

Prof. Jackson: That depends upon the arrangement of the mill itself. It is seldom that a motor would be applied to a single set of rollers; the mill may be divided into several sections, to each of which a motor is connected, or a single large motor driving the entire mill may be used. External circumstances often control this question.

Mr. Coster: We have recently submitted a proposition on a 900-horse power motor engine, 150 revolutions per minute, for driving a flouring mill, the motor, probably, to be installed within the next six months.

A Member: That would apply to the general line of shafting, the same as this?

Mr. Coster: Yes, that would apply, but this mill is driven by water power, but sometimes the water power gets low and then they use a motor driven by electricity.

Mr. Johnston: At Portland, Oregon, there is a flour mill of 1800 barrels a day capacity operated by an electric motor-the capacity of that is 1400 kilowatt. That I saw last winter, and is

giving very satisfactory service.

XXXV

GAUGING OF STREAMS.

By WILLIAM G. PRICE, Mem. W. S. E.

Read May 18, 1898.

The writer will not undertake to describe all the methods of veocity measurements now used, but will give a description of some of the methods which have been used by him during the past nineteen years.

So much has been written upon this subject that very little is left to be said, except to describe more in detail the work of discharge observation.

The experience of the writer began in the year 1879, on the lower Mississippi River, where attempts were made to use the Ellis and Herschel current meters. It was soon seen that these meters were not adapted for use in sediment bearing streams where sand cut the bearings of the Ellis, and floating leaves and grass clogged the wheel of the Herschel. The discharge was

measured that year with double floats, and required four observers on shore, one at each of the three range lines, 100 feet apart, and one to take angles, besides two skiff parties, one to put out the floats and one to take them in again. At first the observers at the range lines were to call time as the float passed the range, loud enough so one of them could time the float with a stop watch and the man at the instrument at the end of the base line could take the angle to locate the position of the float in the river. When the work began one of the observers at one of the ranges, who stuttered, was unable to say time just when the float was on the line, although he made heroic efforts to do so. A telegraph system was then installed and each observer had only to press a key at the proper instant. The method with double floats was not very satisfactory. Owing to the eddies and boils, the lower float was sometimes ahead of, and sometimes behind the surface float, and as the upward current in the boils was very strong, it is probable that the lower float was at times near the surface. There were four observers on shore, and the accuracy of the work depended on each of these observers, as well as on the man who adjusted the length of string between the surface and the sub-surface floats. One careless man could render the whole work inaccurate, and the chief of the party had no check on anyone. Notwithstanding these defects in the method, the work done was remarkably good for the time and place.

The next year several parties began work on the upper Mississippi River. The first work was to measure the discharge during

the winter, through the ice, using the Ellis current meter, which in the hands of an expert could be made to do good work in clear water. The meter was first rated in a lake of still water, through the ice. To do this successfully an opening should be cut in the ice, one foot wide, and about 250 feet long. The meter should be attached to its rod and weight, and suspended two or three feet below the ice, from a sled which straddles the opening, and which carries the observer with his battery, register and stop watch. The ice must be made level where the sled runners are to pass, so the meter will be carried without any up and down movement. A base line of 200 feet should be measured along the opening, and each end should be marked by a range made by two flags at right angles with it. The sled should be drawn back and forth at low, medium and high velocities, the stop watch and register being started on the first range line, and stopped on the second. Several ratings like this were made by the writer during the winter of 1880-81. When using the meter in winter it is necessary to protect the suspending rope and insulated wire from freezing, otherwise they will become so coated with ice that they cannot be manipulated. The method used by the writer on the Mississippi and Missouri rivers was to build a small house on a sled. The house was just large enough for one man to sit inside, leaving room at one end for a very small stove and room at the other end to lower the meter into the water through a trap door. The sled had board runners, curved to run forward and back, and had a rope at each end to draw it by. The house consisted of a light wood frame, which was covered on sides and top with heavy canvas, and had a canvas door, all of which was given one -coat of linseed oil. A reel near the roof, at one end, carried the steel meter suspending rope and insulated wire. The shaft of the wheel passed through the side of the house, and there was a crank ratchet and pawl on the outside. The suspending rope and insulated wire were each connected with copper rings on the reel, and springs made contact with these rings and completed the electric circuit to the meter, register and battery. Two men were required to measure a discharge, one to sit inside and record the soundings, registrations and time, and the other to cut holes in the ice, draw the sled, feed the fire and turn the outside crank when the meter was to be raised and lowered. Holes were cut in the ice in a line across the river, and measurements were taken through each at mid-depth, for the discharge. Many vertical velocity measurements were also taken, so as to determine the correction required to reduce the observed mid-depth velocity to the mean velocity.

This work was continued on the Mississippi until on the 6th of April the ice started with our party in the middle of the river, and we had to get to shore by jumping from one cake of ice to another. One problem which at first seemed difficult was to measure the height of the water which was required each day be

If a post was

fore and after the measurement of the discharge. driven into the ground through a hole in the ice, and the gauge board was nailed to it, the ice would freeze to it in a few hours and a rise or fall of the river would lift or pull down the post, and then the ice had to be cut off of the gauge board twice a day so it could be read, and the graduations were likely to be cut off at the same time.

One chief of party, who was making heroic efforts to secure correct gauge readings when the temperature was 30 degrees below zero, finally wrapped up the gauge post with a fine wool blanket with the lower edge of the blanket in the water. This surely was expected to keep the gauge warm, but much to his disappointment, the next morning the blanket was solid ice, and had to be chopped away also. The best plan is to cut a hole in the ice where the water is about four feet deep, and then drive a stake through the hole into the ground, using a follower till the top of the stake is below the bottom of the ice. Level from the top of the stake to a bench mark, and read the gauge with a small graduated rod, the end of which has a board about four inches square nailed to it so it will be easy to find the top of the stake and rest the rod upon it. Of course the hole in the ice has to be chopped open every day, and the graduated rod has to be taken into the house and the ice melted off of it after each reading of the gauge. After the ice was gone the discharge was measured with rod floats. A wire anchorage was first placed across the river. The cross wire was of No. 10 steel, and it was supported from being carried down the stream by the current at points 80 feet apart by anchor wires, which led up stream to large stone anchors. The anchors weighed 250 pounds, and the length of each anchor wire was five times the depth of the water. The cross wire was made in links 80 feet 4 inches long, which were joined by a two inch ring of 4 inch round iron. The anchor wires were attached one to each ring. This made the stations for discharge measurements 80 feet apart, as the 4 inches was required for down stream sag in the wire between stations.

When not in use the wire lay on the bed of the river, and the movement of sand reefs down stream would occasionally bury it so deep it required a hard pull to lift it up again. It had to be raised every day during high water to keep it from becoming buried too deep in the sand, and to remove the large mass of leaves and grass which moved along the bottom of the river and col. lected upon it. In lifting the anchorage it was under-run by a skiff which passed from shore to shore in opposite directions each day; as the slack in the wire followed the skiff it could not be under-run twice in one direction without breaking it.

In places where the cross wire was suspended a few inches above the bottom of the river, the sand in suspension in the swift current would collide with it, and would cut the metal away so fast it had to be renewed several times during the year.