Chapter X: TECHNOLOGY.--The Manufacture of Cocaine--The extraction (2)

It was intended that great care should be taken in driving the spikes, that they were in the proper place, square with the rail, and left sticking up about an inch.

The ties, of course, were all adzed down before the day of change.

"Handspikes" were originally used to throw the rails, as were lining bars.

We found, however, that small "cant hooks" were more easily handled and did better work. The first were made like Fig. 38, with a spike in the end of a stick, while the hook was fastened with a bolt about 10 or 12 inches above the foot.

We afterward made them of a 1¼ in. rod, 3½ ft. long, pointed at one end, with a ring shrunk on 1 ft. from the bottom. Then the hook was made with an eye, as shown in Fig. 39, which slipped down over the top of the main rod. This was simple and cheap, and the iron was to be used for repair purposes when this work was done.

Upon the system with which the writer was connected we had some branches where we could experiment upon the moving of the rail. Between Selma and Lauderdale the traffic was light, and at Lauderdale it connected with the Mobile & Ohio Railroad, which was narrow, and to which all freight had to be transferred, either by hoisting the cars or by handling through the house. By changing our gauge we would simply change the point of transfer to Selma. Here was a chance to experiment upon one hundred miles and cause little trouble to traffic. We could see the practical workings of our plans, and, at the same time, leave less to do on the final day. Upon the 20th of April we did this work. It had been our plan to do it somewhat earlier, but floods prevented.

Most of the rail was old chair iron, short, and consequently more time was used in making the change than would have been required had our work been on fishplate rail. Our sections here were about eight miles long, and we arranged our men on the basis blocked out by the committee, viz., 24 to 26 men to the section, consisting of 6 spike pullers, 4 throwing rails, 12 spikers, 2 to push the cars and carry water.

We soon found 5 ft. cars useless, and threw them into the ditch to be picked up at some future time.

The men were spread out so as not to be in each other's way, and when the organization was understood and conformed to, it worked well. One gang changed 5 miles in 5 hours and 10 minutes, including a number of switches. We found, however, and it was demonstrated still more strongly on later work, that after 5 or 6 miles the men began to lag.

We believed we had the best results when we had sections of about that length.

It was arranged that two sections, alternately, commenced work together at one point, working from each other and continuing until the force of another section was met, working from the opposite direction.

The foreman in charge was expected to examine the work and know that all was right. The push car which followed was a good test as to gauge.

A work train was started from each end with a small force (20 or 25 men) to run over the changed track. This train, of course, had been changed on a previous day to be ready for this work.

If a force was overtaken by this train with its work not done, the men on the train were at once spread out to aid in its completion. This done, the train ran on.

Not until this was done was a traffic train allowed to pass over the track. The same rule was followed upon all the work.

Upon the final day it was required that upon all high trestles and in tunnels the track should be full-spiked before being left or a train let over. This took extra time and labor, and possibly was not necessary; but it was a precaution on the side of safety.

Upon the day of the change of the Alabama Central Division (Selma to Lauderdale), superintendents of other divisions, with their road masters, supervisors, master mechanics and many section foremen, were sent over to see the organization and work and the preparations that had been made. Many of them lent a helping hand in the work. They saw here in practice what had only been theory before.

About a week before the general change that portion of the road between Rome, Ga., and Selma, Ala., about 200 miles, was changed, and again men from other divisions were sent to see and aid in the work. So when the final day came, the largest possible number of men were able to work understandingly.

On the last day of May the Memphis & Charleston, Knoxville & Ohio, and North Carolina branch were changed, and on June 1 the line from Bristol to Chattanooga and Brunswick.

Other roads changed their branch lines a day or two before the 1st of June; but the main lines, as a rule, were changed on that day.

It was a small matter to take care of the cars and arrange the train service so there should be no hitches. It was not expected that connections would move freight during the 48 hours prior to the change, and these days were spent in clearing the road of everything, and taking the cars to the points of rendezvous. All scheduled freight trains were abandoned on the day prior to the change, and only trains run _to_ such points.

Upon the East Tennessee system these points were Knoxville, Rome, Atlanta, Macon, Huntsville, and Memphis, and to these points all cars must go, loaded or empty, and there they were parked upon the tracks prepared for the purpose. Passenger trains were run to points where it had been arranged to change them, generally to the general changing point.

Most of the Southern roads have double daily passenger service. Upon all roads one of these trains, upon the day of change, was abandoned, and upon some all. Some, even, did not run till next day.

We were able to start the day trains out by 10 or 11 o'clock A.M., and put them through in fair time. Of course, no freights were run that day, and the next day was used in getting the cars which had been changed out of the parks and into line. So our freight traffic over the entire South was suspended practically three days.

The work of changing was to commence at 3:30 A.M., but many of the men were in position at an earlier hour, and did commence work as soon as the last train was over, or an hour or so before the fixed time. Half-past three A.M., however, can be set down as the general hour of commencement.

For five or six hours in the cool morning the work went on briskly, the men working with much more than ordinary enthusiasm. But the day was warm, and after 9 or 10 A.M. it began to lag. All was done, however, before the day was over, and safe, so that trains could pass at full speed.

The men all received $1.50 for the work, whether it was finished early or late in the day, and were paid that afternoon as soon as the work was done. Tickets were given the men, which the nearest agent paid, remitting as cash to the treasurer.

On some lines it was deemed best to offer prizes to those who got through first.

Reports showed some very early finishes. But the facts seem to have been that under such encouragement the men were apt to pull _too many_ spikes before the change and put _too few_ in while changing. They were thus reported through early, but their work was not done, and they took great chances.

It was by most considered unwise to offer such prizes, preferring to have a little more time taken and be sure that all was safe. Such lines seemed to get their trains in motion with as much promptness as others. This, with freedom from accident, was the end sought.

It was found after the work had been done that there had been little inaccuracies in driving the gauge spike, to which the rail was thrown, probably from various causes. The rail to be moved may not always have been exactly in its proper place, and then the template in the hurry may not have been accurately placed, or the spike may have turned or twisted.

Whatever was the cause, it was found that frequently the line on the moved side was not perfect, and, of course, many spikes had to be drawn and the rail lined up and respiked. The more careful the work had been done, the less of this there was to do afterward. With rough track this was least seen. The nearer perfect, the more noticeable it was.

Of course, we all planned to get foreign cars home and have ours sent to us. But when the interchange stopped, we found we had many foreign cars, which, of course, had to be changed. This subject had come up in convention and it had been voted to charge three dollars per car when axles did not need turning, and five dollars where they did. By comparison with the cost of changing, as shown in this paper, it will be seen that to our company, at least, there was no loss at these figures.

The following tables will explain the work done upon the Louisville & Nashville and East Tennessee, Virginia & Georgia systems.

It is to be regretted that the writer has not at hand information regarding other roads, that fuller statements and comparisons might be made and the showings be of greater value.

The figures of the Mobile & Ohio are added, having been compiled from the annual report of that road.

MOBILE & OHIO RAILROAD.
(_Compiled from Annual Report._)

________________________________________________________________________ | | | | | | | Number | Cost of | Cost of | Total |Average| |Changed.| Labor. | Material | Cost. | Cost. | |________|__________|__________|__________|_______| | | | | | | Engines and tenders. | 47 |$ 8,031.42|$ 7,276.86|$15,308.28|$325.70| Pass., bag., ex. cars.| 55 | 439.37| 104.25| 542.62| 9.87| Freight cars, 1,361. }|1,468½ | 5,719.03| 739.57| 6,458.60| 4.40| Freight trucks, 107½.}| | | | | | Lever and push cars. | 143 | 1,427.55| 476.93| 1,904.48| 13.32| | | | | | | | Miles. | | | | | Track (inc. sidings). | 583.5 | 17,109.53| 7,275.14| 24,384.87| 41.79| Bridges. | 583.5 | 1,896.60| 190.00| 2,086.60| 3.58| Track tools. | 583.5 | 170.72| 1,405.74| 1,576.46| 2.70| Shop tools. | 583.5 | 419.70| 2,982.90| 3,402.60| 5.83| Temp. side tracks. | 12.09| 1,958.94| 372.37| 2,331.31| 192.83| Switching cars. | | 1,398.18| 16.50| 1,414.68| | Car hoists. | | 2,499.38| 4,419.34| 6,918.72| | |________|__________|__________|__________|_______| | | | | | | Total cost. | |$41,069.42|$25,259.60|$66,329.02| | Total average cost | | | | | | per mile. | | | | |$113.68| ______________________|________|__________|__________|__________|_______|

LOUISVILLE & NASHVILLE RAILROAD.
(_Compiled from Annual Report._)

Miles of track--Main line 1,893.7
--Side track 196.3
------- 2,090.0
Cost
Track. Total. per Mile.
Section labor--Before day of change $28,106.60
--On day of change 20,090.42
--After day of change 19,713.19
---------- $67,910.21 $32.49
Carpenter labor 3,799.19 1.82
Spikes 20,873.70 9.99
Switches 6,331.85 3.03
Tools 2,749.50 1.31
Hand cars and sundries 5,691.39 2.72
----------- ------
Total $107,855.84 $51.36

_Equipment._
Average
Number. Total. Cost.
Locomotives 264 $53,480.98 $202.58
Cars (300 of these passenger--3.5%) 8,537 49,577.20 5.81
----------- --------
Total cost $210,414.02
Total average cost per mile $100.67

EAST TENNESSEE, VIRGINIA & GEORGIA SYSTEM.

__________________________________________________________________________
| | | | | |
| Number | Cost of | Cost of | Total |Average|
| Changed.| Labor. | Material | Cost. | Cost. |
|_________|__________|__________|___________|_______|
| | | | | |
Engines and tenders. | 180 |$ 8,227.47|$ 2,904.30|$ 11,131.77|$ 61.82|
Pass., bag., and mail | | | | | |
cars. | 168 | 734.93| 59.67| 794.60| 4.73|
Freight cars and | | | | | |
cabooses. | 5,175 | 17,425.57| 1,224.08| 18,649.65| 3.60|
M. of W. cars. | 439 | 2,038.44| 549.47| 2,587.91| 5.89|
| Miles | | | | |
| Track. | | | | |
Track (inc. sidings). | 1,532.7 | 27,718.17| 40,912.09| 68,630.26| 44.78|
Bridges. | 1,532.7 | 1,808.57| 200.00| 2,008.57| 1.31|
Track tools. | 1,532.7 | 194.48| 2,573.83| 2,768.31| 1.80|
Storage tracks, inc. | | | | | |
taking up. | 37.02| 9,825.41| 1,481.59| 11,307.00| 305.44|
Shop tools. | | 472.20| 2,728.30| 3,200.50| |
|_________|__________|__________|___________|_______|
| | | | | |
Total cost. | |$68,445.24|$52.633.33|$121,078.57| |
Total average cost | | | | | |
per mile. | | | | |$ 79.06|
______________________|_________|__________|__________|___________|_______|

Axles condemned 577
Wheels condemned 754
Wheels burst 202
New axles used 1,102
New wheels used 2,783
Axles turned back 8,316
Wheels pressed on without turning axle 23,952
New brasses used 10,723
Cars narrowed (not including lever or push cars) 5,343
Engines narrowed 180
Average cost of new centers and crank pins, etc $264.46
Average cost of cutting off hub and pressing wheels and new pins 130.67
Average cost of pressing old tires on old centers 29.08
Average cost of pressing old tires on broad centers 31.83
Average cost of labor putting on new tires 22.94

COMPARATIVE STATEMENT OF AVERAGE COST OF VARIOUS ITEMS OF WORK.

__________________________________________________________________________
| | | | |
| M. & | L. & | E.T., V.|Average. |
| O. R.R. | N. R.R. |& G. R.R.| |
|_________|_________|_________|_________|
| | | | |
Engines and tenders--per engine | $325.70 | $202.58 | $61.82 | $196.70 |
Pass., bag., and ex. cars--per car| 9.87 |[2] 5.81 | 4.73 | 6.80 |
Freight cars, per car | 4.40 |[3] 5.81 | 3.60 | 4.60 |
M. of W. cars, per car | 13.32 | 2.72 | 5.89 | 7.31 |
Track (inc. sidings bridges, | | | | |
etc.), per mile | 45.37 | 47.83 | 46.09 | 46.26 |
Track tools, per mile | 2.70 | 1.31 | 1.80 | 1.94 |
Temporary side tracks, per mile | 192.83 | | 305.44 | 249.13 |
|_________|_________|_________|_________|
Total per mile of track, inc. | | | | |
sidings | $113.68 | $100.67 | $ 79.06 | $ 97.80 |
__________________________________|_________|_________|_________|_________|

[Footnote 2: Expense not divided as between passenger and freight
cars.]

[Footnote 3: 3.5 per cent. passenger, baggage, and express cars,
96.5 per cent. freight cars.]

NOTE--Since the preparation of this paper the general manager of the Norfolk & Western Railroad has kindly furnished the following items of expense for that line:

___________________________________________________________________
| | | |
| No. | Cost. | Average |
| | | Cost. |
|_________|____________|_________|
| | | |
Engines and tenders | 95 | $37,730.00 | $397.16 |
Cars (all kinds) | 3,615 | 37,994.65 | 10.51 |
Track, miles (including sidings) | 597.5 | | |
Labor | | 25,296.96 | |
Tools and supplies | | 3,531.12 | |
Changing M. of W. equipment | | 813.13 | |
Switches | | 571.67 | |
Spikes | | 8,508.22 | |
| | ---------- | |
Total track | | $38,721,10 | 64.80 |
| | ========== | |
Total | |$114,445.75 |---------|
Total average cost per mile | | | $191.53 |
__________________________________|_________|____________|_________|

And the superintendent of the S.F. & W. R.R. has also furnished the expenses for that road:

___________________________________________________________________
| | |
| No. | Average |
| | Cost. |
|__________|_________|
| | |
Engines and tenders | 75 | $76.31 |
Cars (passenger) | 95 | 4.67 |
Cars (freight) | 1,133 | 3.88 |
Track, including sidings | 601.76 | 44.49 |
______________________________________________|__________|_________|

Nothing was said about shop or other tools, storage tracks, or changing of maintenance of way equipment.

COMPARATIVE STATEMENT OF AVERAGE COST OF
LABOR OF VARIOUS ITEMS OF WORK.
_________________________________________________________________
| M. & | L. & | E.T., V. | |
| O. R.R. | N. R.R.| & G. R.R.| Average|
|_________|________|__________|________|
| | | | |
Engines and tenders. | $170.88}| | {$45.71 | $108.29|
Pass., bag., and ex cars | 7.97}| Not | { 4.38 | 6.17|
Freight cars | 3.89}| divided| { 3.36 | 3.62|
M. of W. cars | 9.98}| | { 4.64 | 7.31|
Miles track (including | | | | |
sidings, bridges, etc.) | 32.57 | $34.31| 19.26 | 28.71|
Track tools, per mile | .30 | Not | .13 | .21|
Temporary tracks | 162.03 | divided| 265.40 | 213.71|
|_________|________|__________|________|
| | Not | | |
Total per mile of track | $70.38 | divided| $44.72 | $57.55|
__________________________|_________|________|__________|________|

COMPARATIVE STATEMENT OF AVERAGE COST OF
MATERIAL OF VARIOUS ITEMS OF WORK.
_________________________________________________________________
| M. & | L. & | E.T., V. | |
| O. R.R. | N. R.R.| & G. R.R.| Average|
|_________|________|__________|________|
| | | | |
Engines and tenders. | $154.82}| | { $16.11 | $85.46|
Pass., bag., and ex cars | 1.90}| Not | { .35 | 1.12|
Freight cars | .51}| divided| { .24 | .37|
M. of W. cars | 3.34}| | { 1.25 | 2.30|
Miles track (including | | | | |
sidings, bridges, etc.) | 12.80 | $13.02| 26.88 | 17.55|
Track tools, per mile | 2.40 | Not | 1.67 | 2.03|
Temporary tracks | 162.03 | divided| 40.04 | 101.03|
__________________________|_________|________|__________|________|
| | Not | | |
Total per mile of track | $43.30 | divided| $34.34 | $38.82|
__________________________|_________|________|__________|________|

SUMMARY OF STATEMENTS OF L.& N. AND E.T.,
V.& G. RAILWAYS.

The mileage changed of the L&N. and E.T., V.& G.
systems combined aggregates 3,622 miles.
The total cost of these two roads. $331,492.59
Or an average per mile of 91.52
Total miles changed was about 14,500 miles.
Which would give total cost, at same rate. $1,327,040

We should really add to this a large sum for the great number of new locomotives which were purchased to replace old ones, that could not be changed, except at large cost, and which, when done, would have been light and undesirable.

Upon the basis of the work done upon the L. & N. and E.T., V. & G. systems, which, combined, cover about one-fourth the mileage changed, we have made the following estimates, which will, perhaps, convey a better idea of the extent of the work than can be obtained in any other way:

Miles of track changed, about 14,500
Locomotives changed, about 1,800
Cars (pass, and freight) changed, about 45,000
New axles used, about 9,000
New wheels used, about 20,000
Axles turned back, about 75,000
Wheels pressed on without turning axles, about 220,000
New brasses used, about 90,000
Kegs of spikes used, about 50,000
Cost of material used, about $600,000
Cost of labor, about 730,000
Total cost of work, about 1,330,000
Amount expended on equipment, about 650,000
Amount expended on track, about 680,000
Amount expended on track on day of change in labor, about 140,000

The work was done economically, and so quietly that the public hardly realized it was in progress. To the casual observer it was an every day transaction. It was, however, a work of great magnitude, requiring much thought and mechanical ability.

That it was ably handled is evidenced by the uniform success attained, the prompt changing at the agreed time, and the trifling inconvenience to the public.--_Jour. Assn. Engineering Societies._

* * * * *

TORPEDO BOATS FOR SPAIN.

In our present issue, on page 9948, we give illustrations of two torpedo boats, the Azor and Halcon, which have lately been constructed by Messrs Yarrow & Co., of Poplar, for the Spanish government. They are 135 ft. in length by 14 ft. beam, being of the same dimensions as No. 80 torpedo boat, lately completed by the above firm for the Admiralty, which is the largest and fastest torpedo-boat in the British navy.

The general arrangement of these torpedo boats is sufficiently clear from the illustrations to need but little description. Suffice it to say that the engines are of the triple compound type, capable of indicating 1,550 horse power, steam being supplied by one large locomotive boiler, which our readers are already aware is in accordance with the usual practice of the makers, as, by using a single boiler, great simplification of the machinery takes place, and considerably less room is occupied than if two boilers were adopted. It is worthy of record that although in some torpedo boats, and indeed in a great number of them, trouble has been found with the locomotive type of boiler, still we have no hesitation in saying that this is due either to defective design or bad workmanship, and that, if properly designed and constructed, such difficulty does not occur. And it is a fact that Messrs. Yarrow & Co. have already constructed a great number of locomotive boilers of the exceptional size adopted in these two Spanish boats, and they have turned out in every respect, after actual service, perfectly satisfactory.

The forward part of the boat is provided with two torpedo-ejecting tubes, as usual, and near the stern, on deck, it is proposed to place turntables, with two torpedo guns for firing over the sides, as already adopted by several governments. The trials of the Azor took place about two months since, giving a speed during a run of two hours and three quarters, carrying a load of 17 tons, of 24 knots (over 27½ miles) per hour. Since her trial she has steamed out to Spain, having encountered, during a portion of the voyage very bad weather, when her sea going qualities were found to be admirable.

The Halcon, whose official trials took place lately, obtained a speed of 23.5 knots, carrying a load of 17 tons. It may be remarked that a speed of 24 knots, in a boat only 135 ft in length, under the Spanish conditions of trial, is by far the best result that has ever been obtained in a vessel of these dimensions There is, however, no doubt that had the length of the boat been greater, a still higher speed would have been obtained But it was desired by the authorities to keep within the smallest possible dimensions, so as to expose as little area as practicable to the fire of the enemy, it being clearly evident that this is a consideration of the first importance in an unprotected war vessel.

In conclusion, we would add that the hulls of these two Spanish boats are of much greater strength of construction than is usually adopted in torpedo boats, it having been found that for the sake of obtaining exceptional speeds, strength sufficient for actual service has often been injudiciously sacrificed And, judging from the numerous accidents which took place at the recent trials off Portland, we have no doubt that in the future naval authorities will be quite ready and willing to sacrifice a little speed so as to obtain vessels which are more trustworthy. The necessity for this, we feel convinced, will be conclusively shown if ever torpedo boats are engaged in actual warfare, and this not only as regards strength of hull, but also as regards the machinery, which at present is only capable of being handled successfully by men of exceptional training, who in times of war would not be readily procured--_The Engineer._

* * * * *

THE SPANISH CRUISER REINA REGENTE

In our SUPPLEMENT, No. 620 we gave an illustration of this ship, with some particulars. The interest expressed in naval circles for further information induces us to give still further engravings of this remarkable vessel, with additional information, for which we are indebted to the _Engineer_.

We gave recently a short account of two of the trials of this vessel, and we are, by the courtesy of the builders--Messrs. Thomson, of Clydebank--enabled to lay further particulars before our readers this week. We give herewith engravings of the vessel, which will illustrate her salient points. The principal dimensions are as follows.

Length on water line, 317 ft., breadth, 50 ft. 7 in., depth moulded, 32 ft. 6 in., normal displacement, 4,800 tons, deep load displacement, 5,600 tons. We have before informed our readers that this vessel was designed by Messrs. Thomson, in competition with several other shipbuilding firms of this and other countries, in reply to an invitation of the Spanish government for a cruiser of the first class. The design submitted by the builders of the Reina Regente was accepted, and the vessel was contracted to be built in June of last year. The principal conditions of the contract were as follows.

The ship to steam at a speed of 20½ knots for four runs on the mile and for two hours continuously afterward. She was further to be capable of steaming for six hours continuously at a speed of 18½ knots, without any artificial means of producing draught. She was also to be capable of steaming a distance of at least 5,700 knots for 500 tons of coal, at some speed over 10 knots, to be chosen by the builders. Over the length of her machinery and magazine spaces she was to have a sloping deck extending to 6 ft. below the water line at the side, and formed of plates 4¾ in. thick. This deck was to extend to about 1 ft. above the water line, and the flat part to be 3-1/8 in. thick. Beyond the machinery and magazine spaces, the deck was to be gradually reduced to 3 in. thick at the ends. This deck is intended to protect the vitals of the ship, such as boilers, engines, powder magazines, steering gear, etc., from the effects of shot and shell, but the floating and stability maintaining power of the ship was to be dependent upon a similar structure raised above this protective deck to a height of about 5 ft. above the water.

This structure is covered by a water tight deck known as the main deck of the ship, on which the cabins and living spaces are arranged. The space between the main and protective deck is divided, as may be seen by reference to the protective deck plan, into many strong, water tight spaces, most of which are not more than about 500 cubic feet capacity. The spaces next to the ship's side are principally coal bunkers, and may, therefore, exclude largely any water that should enter. The first line of defense is formed inside these coal bunkers by a complete girdle of coffer dams, which can be worked from the main deck. These it is intended to fill with water and cellulose material, and as they are also minutely subdivided, the effects of damage by shot and consequent flooding may be localized to a considerable extent. The guns of the ship are to consist of four 20 centimeter Hontorio breech loading guns on Vavasseur carriages, six 12 centimeter guns, eight 6 pounder rapid firing, and eight or ten small guns for boats and mitrailleuse purposes, four of which are in the crow's nests at the top of the two masts of the ship. We may remark in passing that the builders saw their way at an early period of the construction to suggest an addition to the weight of the large sized guns, and there will actually be on the ship four 24 centimeter guns, instead of four 20 centimeter. The vessel was to carry five torpedo tubes, two forward in the bow, one in each broadside, and one aft. All these tubes to be fixed. To fulfill the speed condition, four boilers were necessary and two sets of triple expansion engines, capable of developing in all 12,000 horse power.

Now that the vessel has been completely tried, the promises by the builders may be compared with the results determined by the commission of Spanish officers appointed by the government of Spain to say whether the vessel fulfilled in all respects the conditions laid down in the contract. The mean speed attained for the two hours' run was 20.6 knots, as compared with 20.5 guaranteed, but this speed was obtained with 11,500 horse power instead of the 12,000 which the machinery is capable of developing. The officers of the Spanish commission were anxious not to have the vessel's machinery pressed beyond what was necessary to fulfill the speed conditions of the contract; but they saw enough to warrant them in expressing their belief that the vessel can easily do twenty-one knots when required, and she actually did this for some time during the trial.

During the natural draught trial the vessel obtained a mean speed of 18.68 knots, on an average of 94¾ revolutions--the forced draught having been done on an average of 105½ revolutions. The consumption trial, which lasted twelve hours, was made to determine the radius of action, when the ship showed that at a speed of 11.6 knots she could steam a distance of 5,900 knots. Further trials took place to test the evolutionary powers of the vessel, though these trials were not specified in the contract.

The vessel, as may be seen from the engravings, is fitted with a rudder of a new type, known as Thomson & Biles' rudder, with which it is claimed that all the advantage of a balanced rudder is obtained, while the ship loses the length due to the adoption of such a rudder. It is formed in the shape of the hull of the vessel, and as the partial balance of the lower foreside gradually reduces the strains, the rudder head may be made of very great service. As a matter of fact, this rudder is 230 ft. in area, and is probably the largest rudder fitted to a warship. The efficiency of it was shown in the turning trials, by its being able to bring the vessel round, when going at about nineteen knots, in half a circle in one minute twenty-three seconds, and a complete circle in two minutes fifty-eight seconds, the diameter of the circle being 350 yards. This result, we believe, is unrivaled, and makes this vessel equal in turning capabilities to many recent warships not much more than half her length.

* * * * *

FILM NEGATIVES.[1]

[Footnote 1: A communication to the Birmingham Photographic
Society.]

Having had a certain measure of success with Eastman stripping films, I have been requested by your council to give a paper this evening dealing with the subject, and particularly with the method of working which my experience has found most successful. In according to their request, I feel I have imposed upon myself a somewhat difficult task.

There is, undoubtedly, a strong prejudice in the minds of most photographers, both amateur and professional, against a negative in which paper is used as a permanent support, on account of the inseparable "grain" and lack of brilliancy in the resulting prints; and the idea of the paper being used only as a temporary support does not seem to convey to their mind a correct impression of the true position of the matter.

It may be as well before entering into the technical details of the manipulation to consider briefly the advantages to be derived--which will be better appreciated after an actual trial.

My experience (which is at present limited) is that they are far superior to glass for all purposes except portraiture of the human form or instantaneous pictures where extreme rapidity is necessary, but for all ordinary cases of rapid exposure they are sufficiently quick. The first advantage, which I soon discovered, is their entire freedom from halation. This, with glass plates, is inseparable, and even when much labor has been bestowed on backing them, the halation is painfully apparent.

These films never frill, being made of emulsion which has been made insoluble. Compare the respective weights of the two substances--one plate weighing more than a dozen films of the same size.

Again, on comparing a stripping film negative with one on glass of the same exposure and subject, it will be found there is a greater sharpness or clearness in the detail, owing, I am of opinion, to the paper absorbing the light immediately it has penetrated the emulsion, the result being a brilliant negative. Landscapes on stripped films can be retouched or printed from on either side, and the advantage in this respect for carbon or mechanical printing is enormous. Now, imagine the tourist working with glass, and compare him to another working with films. The one works in harness, tugging, probably, a half hundredweight of glass with him from place to place, paying extra carriage, extra tips, and in a continual state of anxiety as to possible breakage, difficulty of packing, and having to be continually on the lookout for a dark place to change the plates, and, perhaps, on his return finds numbers of his plates damaged owing to friction on the surface; while the disciple of _films_, lightly burdened with only camera and slide, and his (say two hundred) films in his pockets, for they lie so compact together. Then the advantages to the tourists abroad, their name is "legion," not the least being the ease of guarding your exposed pictures from the custom house officials, who almost always seek to make matters disagreeable in this respect, and lastly, though not least, the ease with which the negatives can be stowed away in envelopes or albums, etc., when reference to them is easy in the extreme.

Now, having come (rightly, I think, you will admit) to the conclusion that films have these advantages, you naturally ask, What are their disadvantages? Remembering, then, that I am only advocating stripping films, I consider they have but two disadvantages: First, they entail some additional outlay in the way of apparatus, etc. Second, they are a little more trouble to finish than the glass negatives, which sink into insignificance when the manifold advantages are considered.

In order to deal effectively with the second objection I mentioned, viz., the extra trouble and perseverance, I propose, with your permission, to carry a negative through the different stages from exposure to completion, and in so doing I shall endeavor to make the process clear to you, and hope to enlist your attention.

The developer I use is slightly different to that of the Eastman company, and is as follows:

A.
Sulphite of soda. 4 ounces.

To be dissolved in 8 ounces of hot distilled water, then rendered slightly acid with citric acid, then add--

Pyrogallic acid. 1 ounce.
Water to make up to 10 ounces.

B.
Pure carbonate of soda. 1 ounce.
Water to make up in all to 10 ounces.

C.
Pure carbonate of potash. 1 ounce.
Water to make up to 10 ounces.

D.
Bromide of potassium. 1 ounce.
Water to make up to 10 ounces.

I have here two half-plate films exposed at 8:30 A.M. to-day, one with five and one with six seconds' exposure, subject chiefly middle distance. I take 90 minims A, 10 minims D, and 90 minims B, and make up to 2 ounces water. I do not soak the films in water. There is no need for it. In fact, it is prejudicial to do so. I place the films face uppermost in the dish, and pour on the developer on the center of the films. You will observe they lie perfectly flat, and are free from air bubbles. Rock the dish continually during development, and when the high lights are out add from 10 to 90 minims C, and finish development and fix. The negatives being complete, I ask you to observe that both are of equal quality, proving the latitude of exposure permissible.

I now coat a piece of glass half an inch larger all round than the negative with India rubber solution (see Eastman formula), and squeegee the negative face downward upon the rubber, interposing a sheet of blotting paper and oilskin between the negative and squeegee to prevent injury to the exposed rubber surface, and then place the negative under pressure with blotting paper interposed until moderately dry only.

I then pour hot water upon it, and, gently rocking the dish, you see the paper floats from the film without the necessity for pulling it with a pin, leaving the film negative on the glass. Now, the instructions say remove the remaining soluble gelatine with camel's hair brush, but, unless it requires intensifying, which no properly developed negative should require, you need not do so, but simply pour on the gelatine solution (see Eastman formula), well covering the edges of the film, and put on a level shelf to dry.

I will now take up a negative in this state on the glass, but dry, and carefully cut round the edges of the film, and you see I can readily pull off the film with its gelatine support. Having now passed through the whole of the process, it behooves us to consider for a few minutes the causes of failure in the hands of beginners and their remedies: 1. The rubber will not flow over glass? Solution too thick, glass greasy. 2. Rubber peels off on drying? Dirty glass. 3. Negative not dense enough? Use more bromide and longer development. 4. Gelatine cracks on being pulled off? Add more glycerine. 5. Gelatine not thick enough? Gelatine varnish too thin, not strong enough. 6. Does not dry sufficiently hard? Too much glycerine.--_E.H. Jaques, Reported in Br. Jour. of Photography._

* * * * *

HOW DIFFERENT TONES IN GELATINO-CHLORIDE PRINTS MAY BE VARIED BY DEVELOPERS.

The following formulæ are for use with gelatino-chloride paper or plates. The quantities are in each case calculated for one ounce, three parts of each of the following solutions being employed and added to one part of solution of protosulphate of iron. Strength, 140 grains to the ounce.

_Slaty Blue._

1.--One part of the above solution
to three parts of a solution of citrate of ammonia.

_Greenish Brown._
2.--Citric acid. 180 grains
Carbonate of ammonia. 50 "

3.--Citrate of ammonia. 250 grains.
Chloride of sodium. 2 "

4.--Citrate of ammonia. 250 grains.
Chloride of sodium. 4 "

_Sepia Brown._
5.--Citrate of ammonia. 250 grains.
Chloride of sodium. 8 "

_Clear Red Brown._
6.--Citric acid. 120 grains.
Carbonate of magnesia. 76 "

_Warm Gray Brown._
7.--Citric acid. 120 grains.
Carbonate of soda. 205 "

_Deep Red Brown._
8.--Citric acid. 120 grains.
Carbonate of potash. 117 "

_Green Blue._
9.--Citric acid. 90 grains.
Carbonate of soda. 154 "
Citrate of potash. 24 "
Oxalate of potash. 6 "

_Sepia Red._
10.--Citric acid. 80 grains.
Carbonate of soda. 135 "
Citrate of potash. 12 "
Oxalate of potash. 3 "

11.--Citric acid. 108 grains.
Carbonate of magnesia. 68 "
Carbonate of potash. 12 "
Oxalate of potash. 3 "

_Sepia Yellow._
12.--Citric acid. 40 grains.
Carbonate of magnesia. 25 "
Citrate of ammonia. 166 "

13.--Citric acid. 120 grains.
Carbonate of magnesia. 72 "
Carbonate of ammonia. 72 "
Chloride of sodium. 8 "

_Blue Black._
14.--Citric acid. 120 grains.
Carbonate of ammonia. 70 "
Carbonate of magnesia. 15 "

15.--Citric acid. 120 grains.
Carbonate of magnesia. 38 "
Carbonate of ammonia. 44 "

16.--Citric acid. 90 grains.
Carbonate of magnesia. 57 "
Citrate of potash. 54 "
Oxlate of potash. 18 "

17.--Citric acid. 72 grains.
Carbonate of magnesia. 45 "
Citrate of potash. 54 "
Oxalate of potash. 18 "

18.--Citric acid. 60 grains.
Carbonate of magnesia. 38 "
Citrate of potash. 68 "
Oxalate of potash. 22 "

_A more Intense Blue Black._
19.--Citric acid. 30 grains.
Carbonate of magnesia. 18 "
Citrate of potash. 100 "
Oxalate of potash. 33 "

_A Clearer Blue._
20.--Citrate of potash. 136 grains.
Oxalate of potash. 44 "

In the photographic exhibition at Florence, the firm of Corvan[1] places on view a frame containing twenty proofs produced by the foregoing twenty formulæ, in such a way that the observer can compare the value of each tone and select that which pleases him best.--_Le Moniteur de la Photographie, translated by British Jour. of Photo._

[Footnote 1: Does this mean Mr. A. Cowan?--_Translator._]

* * * * *

NOTE ON THE CONSTRUCTION OF A DISTILLERY CHIMNEY.

At a recent meeting of the Industrial Society of Amiens, Mr. Schmidt, engineer of the Steam Users' Association, read a paper in which he described the process employed in the construction of a large chimney of peculiar character for the Rocourt distillery, at St. Quentin.

This chimney, which is cylindrical in form, is 140 feet in height, and has an internal diameter of 8½ feet from base to summit. The coal consumed for the nine generators varies between 860 and 1,200 pounds per hour and per 10 square feet of section.

The ground that was to support this chimney consisted of very aquiferous, cracked beds of marl, disintegrated by infiltrations of water from the distillery, and alternating with strata of clay. It became necessary, therefore, to build as light a chimney as possible. The problem was solved as follows, by Mr. Guendt, who was then superintendent of the Rocourt establishment.

Upon a wide concrete foundation a pedestal was built, in which were united the various smoke conduits, and upon this pedestal were erected four lattice girders, C, connected with each other by St. Andrew's crosses. The internal surface of these girders is vertical and the external is inclined. Within the framework there was built a five-inch thick masonry wall of bricks, made especially for the purpose. The masonry was then strengthened and its contact with the girders assured by numerous hoops, especially at the lower part; some of them internal, others external, to the surface of the girders, and others of angle irons, all in four parts.

The anchors rest upon a cast iron foundation plate connected, through strong bolts embedded in the pedestal, with a second plate resting upon the concrete.

As the metallic framework was calculated for resisting the wind, the brick lining does not rest against it permanently above. The weight of the chimney is 1,112,200 pounds, and the foundation is about 515 square feet in area; and, consequently, the pressure upon the ground is about 900 pounds to the square inch. The cost was $3,840.

The chimney was built six years ago, and has withstood the most violent hurricanes.

The mounting of the iron framework was effected by means of a motor and two men, and took a month. The brick lining was built up in eight days by a mason and his assistant.

A chimney of the same size, all of brick, erected on the same foundation, would have weighed 2,459,600 pounds (say a load of 3,070 pounds to the square inch), and would have cost about $2,860.

The chimney of the Rocourt distillery is, therefore, lighter by half, and cost about a third more, than one of brick; but, at the present price of metal, the difference would be slight.--_Annales Industrielles._

* * * * *

THE PRODUCTION OF OXYGEN BY BRIN'S PROCESS.

Considerable interest has been aroused lately in scientific and industrial circles by a report that separation of the oxygen and nitrogen of the air was being effected on a large scale in London by a process which promises to render the gases available for general application in the arts. The cheap manufacture of the compounds of nitrogen from the gas itself is still a dream of chemical enthusiasts; and though the pure gas is now available, the methods of making its compounds have yet to be devised. But the industrial processes which already depend directly or indirectly on the chemical union of bodies with atmospheric oxygen are innumerable.

In all these processes the action of the gas is impeded by the bulky presence of its fellow constituent of air, nitrogen. We may say, for instance, in homely phrase, that whenever a fire burns there are four volumes of nitrogen tending to extinguish it for every volume of oxygen supporting its combustion, and to the same degree the nitrogen interferes with all other processes of atmospheric oxidation, of which most metallurgical operations may be given as instances. If, then, it has become possible to remove this diluent gas simply and cheaply in order to give the oxygen free play in its various applications, we are doubtless on the eve of a revolution among some of the most extensive and familiar of the world's industries.

A series of chemical reactions has long been known by means of which oxygen could be separated out of air in the laboratory, and at various times processes based on these reactions have been patented for the production of oxygen on a large scale. Until recently, however, none of these methods gave sufficiently satisfactory results. The simplest and perhaps the best of them was based on the fact first noticed by Boussingault, that when baryta (BaO) is heated to low redness in a current of air, it takes up oxygen and becomes barium dioxide (BaO_{2}), and that this dioxide at a higher temperature is reconverted into free oxygen and baryta, the latter being ready for use again. For many years it was assumed, however, by chemists that this ideally simple reaction was inapplicable on a commercial scale, owing to the gradual loss of power to absorb oxygen which was always found to take place in the baryta after a certain number of operations. About eight years ago Messrs. A. & L. Brin, who had studied chemistry under Boussingault, undertook experiments with the view of determining why the baryta lost its power of absorbing oxygen.

They found that it was owing to molecular and physical changes caused in it by impurities in the air used and by the high temperature employed for decomposing the dioxide. They discovered that by heating the dioxide in a partial vacuum the temperature necessary to drive off its oxygen was much reduced. They also found that by supplying the air to the baryta under a moderate pressure, its absorption of oxygen was greatly assisted. Under these conditions, and by carefully purifying the air before use, they found that it became possible to use the baryta an indefinite number of times. Thus the process became practically, as it was theoretically, continuous.

After securing patent protection for their process, Messrs. Brin erected a small producer in Paris, and successfully worked it for nearly three years without finding a renewal of the original charge of baryta once necessary. This producer was exhibited at the Inventions Exhibition in London, in 1885. Subsequently an English company was formed, and in the autumn of last year Brin's Oxygen Company began operations in Horseferry Road, Westminster, where a large and complete demonstration plant was erected, and the work commenced of developing the production and application of oxygen in the industrial world.

We give herewith details of the plant now working at Westminster. It is exceedingly simple. On the left of the side elevation and plan are shown the retorts, on the right is an arrangement of pumps for alternately supplying air under pressure and exhausting the oxygen from the retorts. As is shown in the plan, two sets of apparatus are worked side by side at Westminster, the seventy-two retorts shown in the drawings being divided into two systems of thirty-six. Each system is fed by the two pumps on the corresponding side of the boiler. Each set of retorts consists of six rows of six retorts each, one row above the other. They are heated by a small Wilson's producer, so that the attendant can easily regulate the supply of heat and obtain complete control over the temperature of the retorts. The retorts, A, are made of wrought iron and are about 10 ft long and 8 in. diameter. Experience, however, goes to prove that there is a limit to the diameter of the retorts beyond which the results become less satisfactory. This limit is probably somewhat under 8 in. Each retort is closely packed with baryta in lumps about the size of a walnut. The baryta is a heavy grayish porous substance prepared by carefully igniting the nitrate of barium; and of this each retort having the above dimensions holds about 125 lb. The retorts so charged are closed at each end by a gun metal lid riveted on so as to be air tight. From the center of each lid a bent gun metal pipe, B, connects each retort with the next of its series, so that air introduced into the end retort of any row may pass through the whole series of six retorts. Suppose now that the operations are to commence.

The retorts are first heated to a temperature of about 600° C. or faint redness, then the air pumps, C C, are started. Air is drawn by them through the purifier, D, where it is freed from carbon dioxide and moisture by the layers of quicklime and caustic soda with which the purifier is charged. The air is then forced along the pipe, E, into the small air vessel, F, which acts as a sort of cushion to prevent the baryta in the retorts being disturbed by the pulsation of the pumps. From this vessel the air passes by the pipe, G, and is distributed in the retorts as rapidly as possible at such a pressure that the nitrogen which passes out unabsorbed at the outlet registers about 15 lb. to the square inch. With the baryta so disposed in the retorts as to present as large a superficies as possible to the action of the air, it is found that in 1½ to 2 hours--during which time about 12,000 cub. ft of air have been passed through the retorts--the gas at the outlet fails to extinguish a glowing chip, indicating that oxygen is no longer being absorbed. The pumping now ceases, and the temperature of the retorts is raised to about 800° C. The workman is able to judge the temperature with sufficient accuracy by means of the small inspection holes, H, fitted with panes of mica, through which the color of the heat in the furnace can be distinguished. The pumps are now reversed and the process of exhaustion begins. At Westminster the pressure in the retorts is reduced to about 1½ in. of mercury. In this partial vacuum the oxygen is given off rapidly, and if forced by the pumps through another pipe and away into an ordinary gas holder, where it is stored for use. With powerful pumps such as are used in the plant under notice the whole of the oxygen can be drawn off in an hour, and from one charge a yield of about 2,000 cub. ft. is obtained. With a less perfect vacuum the time is longer--even as much as four hours. The whole operation of charging and exhausting the retorts can be completed in from three to four hours. As soon as the evolution of oxygen is finished, the doors, K, and ventilators, L, may be opened and the retorts cooled for recharging.

The cost of producing oxygen at Westminster, under specially expensive conditions, is high--about 12s. per 1,000 cub. ft. When we consider, however, that the cost should only embrace attendance, fuel, wear and tear, and a little lime and soda for the purifiers, that the consumption of fuel is small, the wear and tear light, and that the raw material--air--is obtained for nothing, it ought to be possible to produce the gas for a third or fourth of this amount in most of our great manufacturing centers, where the price of fuel is but a third of that demanded in London, and where provision could be made for economizing the waste heat, which is entirely lost in the Westminster installation. Moreover, in estimating this cost all the charges are thrown on the oxygen; were there any means of utilizing the 4,000 cub. ft. of nitrogen at present blown away as waste for every thousand cubic feet of oxygen produced, the nitrogen would of course bear its share of the cost.

The question of the application of the oxygen is one which must be determined in its manifold bearings mainly by the experiments of chemists and scientific men engaged in industrial work. Having ascertained the method by which and the limit of cost within which it is possible to use oxygen in their work, it can be seen whether by Brin's process the gas can be obtained within that limit.