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engine, 3 per cent. It is desired to raise ceiving tank, where separation takes the back pressure 6 pounds above its place and from which the water of conpresent point. What must be the cut densation may be pumped back into the off to maintain the same power of the boiler. Short circuiting through the vaengine without raising the boiler pres rious coils and radiators is prevented by sure?
the action of the automatic return valve, The ratio for 1/3 cut-off and 3 per cent which causes each radiator to act indeclearance, according to the table, is .54; pendently of the others. This system is and the mean pressure is (100+15) X.54 especially adapted to large plants and =62 pounds. If the back pressure is where several buildings are connected by raised 6 pounds, the mean pressure must long runs of horizontal pipe. be increased the same amount in order to In the second class of vacuum systems maintain the same power of the engine. the air valves are connected by piping This gives 62+6=68 pounds as the re with an exhauster or ejector, which required mean pressure under the new con moves the air from the radiators, thus ditions. As the boiler pressure is to re allowing the steam to flow in to take its main the same, the ratio between the place. The condensed steam in this case B к
flows to the receiving tank by gravity, as in the common pressure system. An ordinary expansion air valve may be used on the radiators, although a special form designed with reference to a free-dis
charge opening is commonly used. I
The advisability of using a vacuum E
system depends entirely upon the conditions to be met. Where an old heating system, with small supply and return
piping, is to be connected with a power mean pressure and initial pressure will plant to utilize the exhaust steam, it is become 68: 1155.59. Looking at the frequently desirable to install a vacuum table, under 3 per cent clearance, we find system, as in such cases it ordinarily rethat the nearest ratio (which is .60) cor quires from 5 to 10 pounds pressure to responds to a cut-off of 14.
force the steam through the entire sysEngines are usually designed to work tem of pipes and radiators. In old buildmost economically at a given cut-off, so ings where the grading of the returns is that in most cases it is undesirable to faulty, the vacuum system employing a change the cut-off to any extent. Rais pump to draw the condensation back to ing the boiler pressure, on the other hand, the receiving tank is especially desirable. is not so objectionable if the increase One point to be borne in mind in the amounts to only a few pounds.
design of any steam plant, is its simplicBy means of one of the so-called ity; and, when mechanical appliances "vacuum” systems, the exhaust can be such as pumps, traps, automatic valves, used for heating purposes, without rais etc., can be dispensed with without ining the back pressure at all, and in cer terfering with the proper working of a tain cases the pressure may even be re plant, this should be done. duced somewhat below atmospheric pres With properly proportioned and wellsure.
graded pipes, the pressure required for Vacuum systems are of two general circulating the steam through a heating classes. In one, the radiators have two system, even of large size, should not exconnections ; but the usual hand valve on ceed 2 pounds; and the work is often the return is replaced by a special auto done at one pound or less. Now, the matic valve, which opens when in con back pressure on an engine exhausting tact with water or air and closes as soon into the atmosphere is usually about two as steam strikes it. The returns are pounds, so that practically no additional gathered into a single main, and ar load is put upon the engine when the exnected with a vacuum pump, which de haust is used in a well-designed heating livers the condensation and air into a re system : the system simply acts as a large
condenser in which condensation takes place under a slight pressure instead of in a vacuum.
We found, in the first example given, that the increase in boiler pressure required to raise the back pressure from 2 pounds to 5 pounds was only 5 pounds, an amount so small that it could involve no harmful or wasteful results. So far as the efficiency of the radiators is concerned, it makes difference whether the air is drawn out or forced out, provided that the radiators are steam-filled; and, as the temperature increases with the steam pressure, the heating capacity of a radiator filled with steam under pressure is slightly greater than when steam below atmospheric pressure is used.
Under the pressure system, air valves that are poorly constructed or not welladjusted, may prevent the radiators from freeing themselves of air. Vacuum systems, on the other hand, employ these de
vices. It is as necessary in one case as in the other that the valves be properly adjusted and cared for.
The vacuum system has a large field of its own, and is of much value in cases calling for the special features that it possesses.
In modern plants with pipes of ample size, however, it would seem preferable to rely upon steam pressure for removing air from the radiators, and to rely upon gravity for returning the condensation to the receiving tank, rather than to install special mechanical means for accomplishing the same results.
In any case, before the steam is allowed to enter the radiators it should be freed from oil, as far as possible, by being passed through some form of grease extractor; and, before discharging the water of condensation into the receiving tank to be pumped back into the boiler, it is also well to return this water through a settling chamber in order to remove any trace of oil that may remain.
SCIENCE AND INDUSTRY
So many things have arisen during ports are of a character that indicates a the last twelve months to take up the genuine prosperity. attention of the average
The last few months, with several The Year's Prosperity
individual -such as the bank failures, and a number of industrial
Panama Canal, reciprocity establishments, railroads, and other corwith Cuba, strikes, and other national porations cutting down their working topics—that very few men have stopped forces, the pessimist put in some good to think of the unusual business prosper work. He prophesied that we had startity that has marked the industries of the ed on the down grade, that hard times country during the past twelve months. would be upon us before we knew, but As a rule, we have failed to note the fact, the truth is that our trade exports and because our newspapers have been filled imports were more favorable for 1903 with reports of bank failures, Wall than for the previous year. Street panics, and the constant mutter The excess of exports over imports for ings of labor troubles.
the ten months ended October 31st, was During the early part of last year, the $308,964.053. This was an increase in the Secretary of the Treasury and the lead balance of trade of over $11,000,000. Our ing financial men in the East feared that export trade for the ten months showed when the great interior section of the the extraordinary increase of $62,202,country withdrew money from the New 021. A nation that sells more goods York banks to move the crops, the result abroad month by month, need have little would play havoc with the money market. fear of an immediate industrial crash. Strange as it may seem, the crops have Our imports of foreign merchandise been moved without the slightest dis for the ten months up to the 31st of Octurbance of existing conditions. It is also tober showed an increase of over $51,encouraging to note that the Treasury re 000,000, This is another indication of
prosperity, for when times are hard and money scarce, imports from foreign countries are the first to be reduced. The actual available cash balance in the Treasury on the 31st of October amounted to the enormous sum of $223,144,309.
kiosks along the route, without taxation; and the placing of benches and chairs, for which the contractors may charge a certain price. A similar charge is now exacted along the existing boulevard.
8. It subsidizes the undertaking with 11,000,000 pesetas ($2,123,000), payable, with interest, in four installments.
A grand boulevard is soon to be built through the crowded quarter of the old
Another Oppor- city of Madrid; and this tunity for Ameri-m odern improvement,
can Enterprise which is started by the Spanish government, offers a fine opportunity for profitable investment to American capitalists. There are several reasons why the state has undertaken this enterprise, among them being the terribly crowded condition of the old quarter of the town, and the wish on the part of the officials to build up suburbs. The authorities also recognize the importance of improving the sanitary conditions of the city.
The plans of Architect J. L. Sallaberry have already been accepted by the government, and the Gran Via will soon be built. The following is the manner in which the government has subsidized the enterprise :
1. It grants eight years to the contractors in which to complete the work, and provides no penalty if the work is not finished within the specified time.
2. It sells to the contractors all the properties, inclusive of buildings, along the line of the projected boulevard, at the present rate of depreciated values, for which the properties have already been condemned.
3. It exempts forever from increased taxation the properties so acquired, after the boulevard shall be built.
4. It exempts forever the properties so acquired, from the 4 per cent sale and resale tax, which must be paid on all real estate sold.
5. It grants the contractors exclusively a perpetual franchise for a street-car and electric-plant system on the boulevard, which system is to be a mile in length, the franchise to continue at the pleasure of the contractors.
6. It permits the erection of ninestory buildings on both sides of the boulevard, and exempts the owners from taxation on modern improvements.
7. It permits the construction of
While the United States is showing a satisfactory increase in many important
branches of industry, and Our Merchant is invading with a large Marine
measure of success the markets of the Old World, we seem to be overlooking the fact that as a sea power—not referring to our engines of war, but to our merchant marine—the United States is far behind the other nations of the world, and is showing a decrease in tonnage each year.
An excellent editorial in Marine Engineering states:
"In 1810, when the population of the United States was about seven millions, 91.5 per cent of our foreign trade was carried in American ships of a gross tonnage of 981,000 tons. Forty-nine years later, at the outbreak of the Civil War, the proportion of our foreign commerce carried in American bottoms had decreased to 65.2 per cent, but the tonnage had increased to 2,496,000 tons. Now let us consider the discouraging statement of shipping for the past year. The tonnage in our foreign carrying trade has dwindled to 873,000 tons; we carried but 8.8 per cent of our foreign commerce; and moreover, not a single keel for a deepsea ship has been laid in this country for two years.
It is difficult to realize the truth of these facts at a time when other industries are prospering and we are looked upon as the leading producing and manufacturing country of the world. Transportation by sea has, of course, necessarily kept pace with industrial expansion, and the British have been quick to realize the opportunity; their foreign tonnage has now assumed the enormous figure of 14.800,000 tons. Germany comes next with 2,960,000 tons. France and Norway have each about one-half of Germany's tonnage, and Italy's amounts to 1,180,000. The United States is paying annually foreign steamship corpora
tions one hundred millions of dollars for carrying our freight and passengers.
“These facts and figures are more than surprising. They will come as a revelation to the average American. They call for immediate investigation, and a remedy that will save our merchant navy and increase our shipyards."
Some time ago, an interesting article appeared in the Edinburgh Review unAmericanizing der the caption of "Amer
Scotland's icanizing Edinburgh In-
We quote the following to show how American methods are winning their way abroad:
"The ‘one-break' system is another American idea which has gained a footing in this country and is rapidly growing in favor. By this arrangement the breakfast hour is done away with, and the men start work at 7 or 8 o'clock in the morning, having had a good meal, there being only one break during the rest of the day, for dinner. It is contended that this is a much better method, for both men and masters. The men do not start hungry; and being therefore fresher and better rested, they are able to pay more attention, and consequently turn out more and better work. Then, again, the waste,
waste, inconvenience, and delay caused by stopping, restarting at breakfast time, the annoyance of men coming in late, and the other evils of the twobreak system, are done away with; the output is increased; and the men healthier and physically more fit to undertake the duties of the day. The onebreak system was first introduced into Great Britain by a Leeds firm in April, 1901, and was quickly imitated by another firm in the same town. The workmen at first raised an objection, on the ground that the day was too long to work with only one break, and asked either for a reduction of hours or a withdrawal of the system. The matter was subsequently discussed at a central conference of the Engineering Employers' Federation, where it was stated that 83 firms throughout the country, of which 26 were federated firms, had adopted the system, and were on an average working a 51-hour week. The experience of these firms, it was stated, was that the work
them, preferred the altered hours. In 13 firms the hours were divided as follows: Monday, 8 A. M. to 6 P. M., with the dinner hour from 12 to 1 o'clock; Tuesday, Wednesday, Thursday, and Friday, 7 A. M. to 6 P. M., with the dinner hour at the same time; Saturday, 7 A. M. till noon—a total of fifty-four hours. Of course, these new methods of premiums and the one-break system are applicable to any profession, and, indeed, the latter is in use in many other professions in Edinburgh.”
An interesting comparison was made the other day between the speed of EngSpeed of English lish and American rail
and American road trains. The followRailroad Trains ing table sets forth the runs of eight English trains, indicating an average speed of between 50.3 and 61.7 miles an hour :
Min- Speed Company and Run. Miles. utes. per hr. Northwestern, Darlington to York.......
4174 43 61 7-10 Midland, Appleby to Carlisle..........
3034 30 61 5-10 Caledonian, Forfar to Perth......
32/2 32 60 9-10 Great Western, Bristol to
Paddington. .........11774 120 58 6-10 London & Northwestern,
Birmingham to Euston.....113 120 56 5-10 Great Central, Aylesbury to Leicester..
65 69 56 5-10 Great Northern, Wakefield
to King's Cross...... .17534 190 55 6-10 London & Southwestern, Salisbury to Waterloo....... 83% 91 55
It is somewhat difficult to compare these runs with our American runs. The nearest approaches to them are the following:
Min- Speed Company and Run. Miles. utes. per br. Philadelphia & Reading,
Camden to Atlantic City... 57.8 60 57.8 Pennsylvania, Philadelphia to Atlantic City....
59 60 59 New York Central, Buffalo
to New York......... .400 525 50.28 Lake Shore and New York Central, Chicago to N. Y...980 1,200 48.996
Since the Northern Railway of France discontinued the Paris to Arres Express, the Bristol and Paddington is now the fastest for its distance (11774 miles) in the world. There is, however, nothing in England to match the Twentieth Century Limited of the Lake hore, or the Empire State Express of the New York
U of the memorable series of tests
THE LATEST WORK AT ZOSSEN ning free. The wheels are 49 in. in di
ameter and are equipped with WestingVABLE dispatches just to hand an house pneumatic brakes of the standard nounce the closing for the season type. The transformers, which are hung
beneath the middle section of the car, made on the Zossen Road near
weigh 12 tons, besides which a storage Berlin with high-speed locomotives, at battery of 631 pounds weight supplies the which velocities of over 130 miles an current for lighting purposes. The inhour have been reached.
terior of the car is provided with upDuring the 22 months that have
holstered seats lengthwise along the elapsed since the close of the first experi- sides, and an open railing encloses at ments, the track from Marienfeldt to Zos
each end the space occupied by the sen has been taken up and relaid with driver. new rails weighing 41 kg. (86. I pounds) As to results and observations during per linear meter, resting on heavy spruce the trip, Dr. Walter Reichel, of the railties 22 in. from center to center and
way department of the Siemens-Schuckheavily ballasted with broken basalt. ert Company, says: “After all arrangeThe rails are set on each tie in a steel ments have been made and the military chair, strongly bolted down, and are posts along the line notified, the current joined perpendicularly by beveled joints, is allowed to enter the car at 14,000 volts.
in. in length, held firmly together by We leave Marienfeldt 25 minutes after bolts passing horizontally through the 9; and in starting up the current in each fishplates, so that the effectiveness of a of the four motors, the power is gradcontinuous rail is practically secured. ually raised to about 2,600 hp. The old light rails, which had failed in The feeding point is passed at 80 km. 1901 and were, therefore, taken up, have an hour.
* By the time Mahlow been laid down flat as guard rails, resting is reached (7 km. from Marienfeldt), a horizontally on special cast-iron chairs in speed of 180 to 185 km. has been attained, such a way that the flat, bottom flange of and yet the train runs over the switches the rail stands vertically along the inside at this point without any particular line of each heavy rail and about 2 in. shock. At this speed it is noticed that the distant from the inner edge of its face. current-collecting devices are still runThe track is a nearly level airline ning quietly, and there is, therefore, no throughout its length, except one curve scruple as to further increasing the of 2,000 yards radius near its southern speed. The last resistances are gradualextremity, and is in all respects up to the ly cut out under the load of 2,300 kw., highest standard of modern railway con and the speed rises to the hitherto unstruction. The motors have likewise reached figures, 190 and 195. been improved in various minor details, While traveling at 195 km. an hour but the cars are substantially the same as we noticed two people standing in the when first constructed. The is middle of the track about 800 meters shown in the accompanying figure. Each ahead, apparently most calmly discussing is 22 meters (72.18 ft.) in length and high-speed traction with each other. weighs 90.5 metric tons, or about 200,000 Luckily, they heard the warning whistle pounds avoirdupois. Of this weight 48 of the signal pipe and got out of the way metric tons comprise the body and run just in time. It would not have been ning gear, and 42.5 tons are made up by possible to have stopped the 93-ton car the motors, transformers, and other de within 800 meters, as it requires fully 1 1/2 tails of the electrical equipment. Each km. to come to a full stop, at a braking end of the car rests on a six-wheel bogie pressure of 200,000 kg.
After truck of the American type; and the mo the trip the car was examined very caretors are four in number, one attached to fully and showed very little evidence of the front and rear axle of each truck, the the demands which had been made upon midd' pair of wheels in each group run it. The front of the car is covered with