Chapter XVII: Division Tactics and Supply (2)

_The operations of supply_ from the Service of the Interior to the front are as follows: One or more points are selected in rear of the troops (exceptionally they may be on a flank) having ample communications with the producing districts of the home country, rail or water, or preferably a combination of the two. These points should be so situated as to have ample security from hostile incursion, generally well to the rear. They should be equipped with store-houses, barracks, corrals, shops, etc. To such a point are shipped the supplies of food, ammunition, forage, medical and surgical supplies, and equipment of all kinds, as well as men and animals. This point is known as the base depot. From this base depot to the troops at the front, supplies and reinforcements are sent over the “line of communications.” This line may be either rail or water or both, but in some cases nothing but a wagon road will be available.

The whole is under the charge of the commander of the line of communications. This officer has the necessary staff. He commands the base depot itself, as well as the line of communications, and the troops detached for their security. He is the officer upon whom devolves the duty of forwarding the necessary supplies to the troops at the front. Frequently his influence upon the outcome of the campaign is second only to that of the supreme commander in the field. He should, of course, be under the orders of the supreme commander, though this practice has been by no means habitual in the American service of the past. He divides his line of communications into three services, (a) defense, (b) supply, sanitary and telegraph, (c) military railways.

From the home country to the base depot supplies are transported by rail or water or both; shipments must usually be broken at the base depot, as the supplies must be stored each class in its appropriate place until ready for distribution at the front. From the base depot to the rail or water head is the zone of the line of communications. At this rail or water head supplies are collected into what is known as the “advance supply depot.” The carriers used in this zone are usually directly controlled by the government, while those used for transportation to the base depot are in the general case commercially controlled.[7] The advance supply depot should be maintained as close to the rear of the moving army, as is tactically and otherwise possible. Herein lies the secret of successful administration of the line of communications. If it is kept far to the rear of the troops, there will result immense increase of labor for the draft animals, with consequent loss of animals, destruction of the roads, inadequate supply of the troops and greatly decreased mobility of the army. The positions of the advance depot and of the refilling points are fixed from time to time by the commander of the forces in the field.

[Footnote 7: “In time of war or threatened war, preference and precedence shall, upon the demand of the President of the United States, be given, over all other traffic, to the transportation of troops and matériel of war, and carriers shall adopt every means within their control to facilitate and expedite the military traffic.” Chap. 3591, Vol. XXXIV, U. S. Statutes at Large.]

From the advance supply depot to the troops is known as the zone of the advance. In this zone, supplies are ordinarily hauled in wagons and motor trucks. If rail or water transportation be established or re-established ahead of the advance supply depot, it is of course at all times utilized to the fullest extent. Also motor transport will be utilized when conditions permit. Where wagon transportation is not operative, for any cause, supplies may be hauled by pack animals, coolies, etc. The trains of wagons or motor trucks are divided into classes belonging to the Line of Communications and to the divisions or supply units whatever they be. The management of these latter classes is a part of the tactics of the Division.

The greater the number of lines of communication possessed by an army the better. The confusion incident to the presence of the immense wagon trains in the rear of a large force in the most favorable case is great enough. It is therefore specially desirable that each supply unit (Corps or Division) shall, so far as practicable have its own line of communications either from the base depot itself or certainly from the advance supply depots.

The supply unit here considered is assumed to be the division as given in the F. S. R. It is in fact a body of troops whose length on a single road is from 10 to 17 miles. If the marching column have a length much greater than this, supply limited to a single road (unless it be a good road on which motor transport is practicable) cannot keep pace with the steady advance of the troops, unless occasional days of rest be interposed. Two separate supply services can seldom operate successfully on the same road at the same time.

Up to the advance supply depot the supply of all modern armies is, in general, similar. Beyond this point there are differences. In the American Service, the wagon or motor trains used in this zone are of three general classes. The first is known to most armies as the regimental train, the second as the administrative or supply train, and the third as the general supply column sometimes called the auxiliary train. Regimental and supply trains belong to the Divisions whilst general supply columns belong to the Line of Communications.

The regimental train carries the immediate baggage, cooking utensils, food, forage, and ammunition of the troops. The Field Service Regulations give to these wagons the name field train and combat train. The number of such wagons allowed each regiment is the subject of regulations published from time to time; the more active the campaign, the smaller being the allowance of regimental wagons. Regulations in time of peace tend to increase the allowance of wagons to amounts that can not be tolerated in aggressive campaign. The efficiency of troops in campaign depends on their having as far as practicable daily access to the regimental trains. When the trains are excessive in size, the troops frequently cannot obtain daily access to them and the trains are a drag on the operations. At the beginning of the Civil War, regiments were allowed field trains of 10 to 13 wagons. At the close, the allowance in the Appomattox campaign was 1 wagon per regiment and about the same in the Western Armies. The regiments were of course small. The F. S. R. at present allow to each infantry regiment 12 field wagons. These are habitually divided into two sections: (1) a baggage section carrying baggage; and (2) a ration section carrying rations and grain exclusively, and including rolling kitchens, if supplied. For transportation of baggage each organization is assigned its proportionate space on the vehicles of the baggage section. The field trains are habitually routed on the march in a body, and usually all the field trains of the different regiments are united in a single body as the division field trains, marching in rear of the troops. Combat wagons pertain to each battalion or squadron, etc. They are an integral part of the battalion or squadron, and habitually march with it in the column. Marching into probable action they remain loaded with their combat unit until the last practicable moment, ammunition being issued when it becomes necessary for the troops to separate from their combat trains.

The administrative trains are known in the American Service as the ammunition and supply trains. They carry ammunition, food and forage. The ammunition train (of a division) consists of 6 wagon companies of 27 wagons each, divided into 2 ammunition companies. They carry the artillery and small arms ammunition of the division. A wagon will carry about 100 rounds of light artillery or 30,000 rounds of small arms ammunition. The food for men and animals is carried in a supply train of 126 wagons or 4⅖ wagon companies. Pack trains are attached when required. This supply train carries two days’ food and grain for the division. It is divided into a first and a second section, each carrying a day’s supply of food and grain for the division. The composition of the supply train will be subject to modification to meet conditions due to depletion of the division in campaign and the amount of supplies obtained locally.

The supply and ammunition trains are the carriers generally used from the advance supply depot to the field trains. The wagons are filled at the advance depot (or where that depot is not sufficiently forward, at refilling points) and they follow up the troops. Each day or as often as may be necessary, supplies are issued from these columns to replenish the issues from the field and combat wagons. The supply trains are connecting links between the line of communications and the immediate supply of the troops. From the supply trains to the troops the carriers used are the field and combat trains of organizations. The ration section of the field train carries for each man two days’ field and one day’s reserve ration, and for each animal two days’ grain ration. The soldier carries on his person at least two days’ reserve rations or more, according to the conditions of the case. In the Civil War as well as in foreign wars there are innumerable examples of the soldiers carrying, in cases of necessity as many as four or five or more rations on the person. The _reserve_ ration, is the simplest efficient ration. Its net weight is 2 pounds. The field ration consists of the reserve ration in whole or in part, supplemented by other articles. Reserve rations are consumed only in cases of emergency by order of superior authority. They are renewed periodically to prevent deterioration. The ration issued in the field will depend upon the transportation facilities. Where these are inadequate the ration will usually have to be diminished. Full field rations are issued whenever practicable. Thus the division carries with it, in advance of the supply depot 7 rations, 4 field and 3 reserve. By reducing the ration, by carrying extra rations in place of some baggage, and by living partly off the country, the division can subsist, when cut off from its supply depot for a period much longer than 8 days. The exact length of time will depend on all the circumstances of the case.

In addition to the regimental and divisional supply trains, the Line of Communications must be prepared to maintain, usually, a class of wagon transportation, called the general supply column, whose business is to forward supplies from the advance supply depot to a flying depot or refilling point where the supplies can be reached by the division supply trains operating with the army. It will be shown shortly that the division supply trains must keep up with their units if the operations are to succeed. To this end, the advance supply depot must be maintained closely in rear of the troops; but that the operations of troops be not too intimately dependent on the location of the advance supply depot, the commander of the Line of Communications must be able to place supplies in emergency ahead of the advance supply depot--within reach of the division supply trains. This is accomplished by the use of the general supply columns of the Line of Communications. The constitution of these columns is less the subject of regulation allowance than that of regimental or divisional supply trains. It will vary greatly with conditions whereas the other two classes of wagon trains bear a reasonably fixed relation to the size of the units. The general supply column may consist of army transport or it may be locally hired or impressed. If a large army is operating on a broad front and is limited to a single line of communications by rail or river, it may tend to expedite supply to establish one or more sub-supply depots on the same front with the advance supply depot.

The divisional supply trains and the general supply columns are not usually reduced in numbers, due to the exigencies of campaign, in the same proportion as are the regimental trains. Under recent legislation, all the personnel of the field transport service, most of which was heretofore civilian will now be enlisted--to the obvious improvement of the service.

Fig. XVII[8] illustrates diagrammatically, after the manner of a railroad graphic time table, the movement of supplies during 5 days of a forward march, including a combat, of a division. (Reference 1 inch map, Geological Survey, Gettysburg and vicinity.) A Pennsylvania division, based upon Gettysburg, is marching from Gettysburg to attack a hostile force to the south. The Northern Central Railroad has been interrupted south of Littlestown. It is intended to repair this railroad as rapidly as possible, under cover of the advancing division, for use as a line of communications. The division marches from Gettysburg on the morning of June 2nd, on Emmitsburg, arriving at the latter place shortly after noon, where it camps for the night. Field wagons join the troops, and issue rations and forage for the night. Supply trains following the division halt in rear, north of Emmitsburg. After the issue to the troops the field wagons proceed back to a designated point to which one section of the supply train is forwarded. Here the field wagons replenish and return to their troops. The emptied supply wagons thereupon are sent back to Gettysburg to refill and afterward rejoin the division. They start at 6 p. m. and reach Gettysburg at 10 p. m. That night while the teamsters and animals get some rest, the wagons are refilled at the depot, and at 6 a. m. June 3rd, they again take the road to rejoin the division at the front. Early the same morning the division starts south towards Woodsboro. All its trains are full, but the first section of the supply train is one march to the rear. The division about 2:30 p. m. goes into camp for the night, south of Woodsboro. Here the arrangements of the previous evening are repeated. The field trains issue a day’s supply of rations and forage to the troops, and proceed to the rear where they are met by a section of the supply train; they replenish what they issued. If nothing is purchased locally an entire section of the supply train will be needed to replenish the issues from the field wagons. Habitually, however, every exertion would be made to obtain from the locality all the stores practicable, especially of the weighty forage item. The purchase would be made by the Chief Quartermaster of the division, and from his knowledge of the amount he can obtain locally, he is able at once to determine how many of the wagons of the supply train will be needed to replenish the field trains. Every wagon load of supplies thus purchased locally saves a round trip of a wagon to the advance supply depot.

[Footnote 8: Calculated for a supply train consisting of 3 sections, each containing one day’s supply of rations and forage (grain only), and an ammunition train of 6 wagon companies, 4 of small arms and 2 of artillery ammunition. This is the tentative organization of 1914, but the method indicated may be applied to any given organization of the trains.]

Supply Service - Division

(<i>not drawn to scale</i>)

Ammunition Service - Division]

At 4 a. m. June 4th, the empty section of two wagon companies starts back to Gettysburg to refill. It has 25 miles to go, and it reaches Gettysburg at 7 p. m., having marched all day, except for a halt for rest from 10 a. m. to 2 p. m. Meanwhile the first section, now refilled, has joined from Gettysburg, and again the division has four wagon companies of its supply train filled, as are also field wagons. Meanwhile the troops have not drawn upon the reserve rations on their persons. Up to this time there have been no expenditures of ammunition or medical supplies, and there is nothing, therefore, for the trains containing those supplies to do except to follow the division.

On the morning of June 4th the division meets the enemy, and attacks him near Frederick. As soon as the attack is planned the trains are halted in a place of safety near Woodsboro. Two wagon companies of ammunition, however, are sent forward from Woodsboro, to stations closely in rear of the division in action, for the purpose of maintaining the ammunition supply during the action. The attack terminates successfully, and the division camps for the night on the field near Frederick, the cavalry moving out in pursuit of the defeated enemy. The supply trains come forward from their halting place near Woodsboro. The two wagon companies of ammunition, which replenished the ammunition in the belts of the men and in the wagons of the combat trains on the field of battle, then start for Gettysburg on the afternoon of June 4th to refill. The wounded are transported by ambulance to the field hospitals at Woodsboro, from which point they will be taken to the rear by rail as soon as railroad communication is re-established. The field trains issue to the troops or replace expended reserve rations, and themselves replenish from the supply train. The emptied section of the supply train then proceeds in the early morning of June 5th to the rear to refill. Meanwhile word is received that the line of communications will be extended by rail to Woodsboro, probably during the afternoon of the 5th of June. Orders are accordingly issued at 8 a. m., June 5th, directing the ammunition wagons to return to Woodsboro, and directing the third section of the supply train to stop at Woodsboro to refill instead of proceeding back to Gettysburg. This order is not received by the ammunition companies until nearly noon.

The division continues south on the morning of the 5th, to the Potomac River, where it camps for the night, its supplies being again issued, as before. The division then rests for the 6th of June, and the railhead is pushed forward to Frederick, closely in rear. The state of the division supply is then as follows (on June 6th); one section of the supply train with the division, another loaded section has just arrived at Frederick from Gettysburg, and a third is filling at the railhead at Frederick. The field trains and the men’s packs are filled. Of ammunition supply, the men’s belts and the combat trains are filled, two wagon companies of small arms ammunition and one of artillery ammunition are with the division, while two other wagon companies, one of each class of ammunition, are en route back to the division from Woodsboro, where they refilled.

It will readily be apparent that with but three sections of the supply train the division cannot move far from its advance supply depot without falling behind in its supply if dependent on wagons. Or stated differently, the supply depot must not be permitted to lag behind the advance of the troops. The relations between steadily advancing troops and the advance supply depot which are necessary to the maintenance of a satisfactory state of supply, may be expressed in a simple way, mathematically, as follows:

Let
n = the number of sections in the supply train, each
containing one day’s supply for the troops.

e = number of miles empty wagons can travel in one day.

f = number of miles loaded wagons can travel in one day.

y = average daily advance of the troops.

X = number of marches (day’s travel) to the rear for empty
wagons to reach the supply depot, average.

Then

ex = miles travel to rear by empties in one trip.

ny = miles the division advances between issues from the same
section, assuming that the sections issue in regular
rotation.

ex + ny = miles traveled by any section from the time it
loads to the time it issues.

This must equal the miles traveled loaded.

Therefore

ex + ny = (n - x) f =1=

f - y
x = n ----- =2=
f + e

x
y = f - --- (f + e) =3=
n

f + 3
n = x ----- =4=
f - y

The maximum marching capacity of the trains, round trip, (that is from point of issue to next point of issue) is ex + (n - x) f.

The distance they _must_ march to overtake the division is 2ex + ny.

Hence
ex + (n-x) f > 2ex + ny

(n-x) f > ex + ny.

Let us now assign actual values to the various quantities, and solve for x.

Make n = 3; f = 20; e = 28; y = 12.

Then the inequality reduces to

x < ½ march of an empty wagon, or x < 14 miles.

This is to say that if the troops advance steadily every day, at the rate of 12 miles, and have 3 supply sections to serve them, and if those sections can travel empty and loaded at the liberal rates of 28 and 20 miles per day, respectively, then the advance supply depot, or refilling point must not lag farther to the rear than 14 miles, or slightly more than one day’s march of the division, unless the division is to draw supplies locally, or fall behind. How are these figures reconciled with known practice? In campaign the troops subsist to the utmost from the local resources along the line of operations. Moreover large bodies do not keep up a rate of advance of 12 miles per diem long. There are rest and combat periods, etc., which reduce y (in foregoing discussion.)

Equation 2 may be considered an expression of the supply train radius somewhat similar to the war ship’s steaming radius. For, let us assume the Division is stationary; then y = O and from Equation 2 we have x = ₆₀/₄₈ = 1¼. Hence the conclusion that when the Division is _stationary_, the supply depot cannot be in rear more than 1¼ marches of an empty wagon (35 miles for the value assumed above). The radius of the supply train can be increased by having the field train go well to the rear to meet it for refilling after the daily issue of rations in camp.

Generally speaking, the refilling points should be kept within two marches of the rear of the troops, if the latter are subsisting chiefly from their base and are supplied by animal-drawn vehicles. If the rail or water head cannot keep thus close, the operations of the forces may be restricted and their mission may be frustrated, unless motor transport be employed.

In order to keep the advance supply depot well to the front the commander of the line of communications must maintain an ample and efficient railroad or steamboat force for operation and for maintenance and repair. This work pertains solely to the line of communications personnel, and if the fighting troops are detached for repair work on the line of communications the operations of the fighting forces cannot fail to suffer.

The field bakery on the Line of Communication does not attempt to keep pace with all the changes of the advance supply depot in a rapid advance. Too much time would thereby be lost. When the bakery _does_ change station, reserves of baked bread should be provided beforehand.

It may be laid down as the ideal condition for supply in campaign that the supply trains be always full, and never drawn from. How can such ideal be approximated? 1. By living off the country, the field trains every day drawing their supplies direct from the collection depots. 2. By maintaining the advance supply depot so close to the troops that the field trains may draw direct, or 3. By a combination of 1 and 2. Another desideratum is that the reserve rations in the men’s packs be not used oftener than is necessary to keep them from spoiling. These two ideals give the daily rules of conduct for supply officers in campaign. A portion of a supply train, when empty, has no status with the command. The first duty of an empty supply train is to proceed to refill and rejoin as soon as practicable. Similarly packs should not be permitted to remain depleted, but should be refilled at the first opportunity. The service of supply is considered good when the transportation with the troops is kept at a minimum, and military operations are not hampered by lack of food and other necessary supplies.

In Sherman’s campaign from Chattanooga to Atlanta, 136 miles, the following places were successively used as advance supply depots: Ringgold, Dalton, Resaca, Kingston, Allatoona, Acworth, Big Shanty, Marietta. Counting Allatoona, Acworth and Big Shanty as a single depot (they were on a single front) we find that the extraordinarily vigorous railroad construction enabled the advance supply depot to be pushed ahead six times; that these moves averaged 23 miles. The depot was thus habitually within two marches of the troops. At Resaca and again at Marietta Sherman accumulated a great quantity of supplies as a precaution against his line being cut at points farther to the rear. These depots and the critical portions of the railroad had to be guarded constantly against the raids of the Confederate cavalry and the intense hostility of the inhabitants. At Resaca, Kingston and other points, where the tactical situation, and the condition of the railroad permitted, supplies were carried forward by rail ahead of the advance supply depots, and issued directly to the field wagons, thus keeping intact the rolling reserve in the supply columns. Grant’s '64 campaign against Lee exhibits similar activity under different conditions. His line of communications was the open sea, and he utilized 5 depots, to wit: Alexandria, Aquia Creek, Port Royal, West Point, City Point, thus keeping within two or at most three marches of the troops.

The operations of the forces should be conducted so as to cover at all times the advance depot. If the forces be cut off from their supply depot and be unable to regain it, disaster must result. Where, therefore, maneuvers to a flank are attempted, that necessarily tend to uncover the supply depot, it is well that the depot be not too close to the forces, and that it be well protected against raids, etc.

(_not drawn to scale_)]

In the advance, the supply trains will ordinarily halt for the night about half a march in rear of the division. The baggage section of the field trains and one day’s ration from the ration sections join the troops without delay, so as to provide the rations and utensils for the preparation of supper. The baggage of the troops though reduced to a minimum in campaign, is essential to the maintenance of their fighting strength, hence the field wagons should always be permitted to join the troops unless the tactical situation positively forbids. As soon as practicable after the arrival in camp of the ration vehicles, they are unloaded and, without delay, rejoin the grouped portions of the ration vehicles. The baggage sections usually go to the same place early the following morning. Empty ration vehicles at the time designated in administration orders, proceed to the distributing or issue point for the purpose of replenishing their supplies. This point is selected in rear of the division, both for safety, and convenience, and because it tends to equalize the travel of the field and supply trains. It should be at some place easily described in orders. A road junction is desirable as it facilitates approach and departure and affords space for the movements of wagons. The distributing point may be at the camp of the supply train, or it may be a point in advance thereof. In the latter case the necessary wagons of the supply train are sent forward to make the issue. It is essential that this point of issue shall lend itself to an orderly issue without delay or confusion amongst the wagons. Cavalry operating at a distance from the division must usually expect to live off the country. A pack train may accompany the cavalry when it is undesirable or impracticable for them to take their wagons, or the cavalry may impress or hire wagons. Cavalry draws ammunition from any source most convenient.

Issues of ammunition are made in essentially the same way as that of rations, from the ammunition train to the combat wagons, at ammunition distributing stations. The issues are not made regularly however as are rations, but only as ammunition is expended.

The time and place of issue must be published to the command, in operation or routine orders. When the local conditions permit, time may be gained by having the wagons unload at the place of issue without awaiting the arrival of the field wagons, and thence proceed at once back to the advance supply depot. Supply trains are under the command of an officer detailed for the purpose.

Figure XVIII issued by the War Department is intended to illustrate diagrammatically the method of supplying troops in campaign.

Supply trains are commanded by officers detailed for the purpose. On the march trains are made up to follow the division in the order of their probable need for the day. If no combat is probable the field trains would be at or near the head and the field hospitals near the tail. If combat seems probable some ammunition should be held well toward the head of the combined trains. For convenience of march trains may be divided into two sections with an interval. A convenient arrangement for an ordinary march, where combat is not probable, is in two sections, as follows: 1st section. Field trains, 1st section supply train, 1st ammunition co., engineer train. 2nd section. Field hospitals, 2d ammunition co., 2d section supply train, pack train. The first section may follow the troops at from 1 to 3 miles, and the second section follow the first at from 1 to 2 miles.

Where danger threatens in front so that combat appears likely, the trains should be halted well to the rear. They may be halted on the road, or parked off the road at the place of receipt of the order, if sufficiently well protected in such place, and if they are not thereby a menace to the safety of the command. They should not be allowed to pass a defile until the conditions on the far side are known to be safe. During combat they should never be permitted to remain on the hostile side of a river or defile, even if it be necessary to leave them many miles to the rear. The necessary ammunition and sanitary supplies are of course sent forward for their appropriate use in the combat. In making a flank march the trains may be held closely in rear in a single section, but if the danger be at all great it will be safer to route the trains, with or without a guard, according to circumstances, on a separate road on the unexposed flank. In a retrograde movement the trains precede, usually alone but with a guard if a flank is exposed. The field trains and the section that is to make the next issue must not be sent too far away from the place where it is intended to camp until the resupply is accomplished. In retreat the service of supply is simplified.

The rate of march of a wagon train depends upon the condition of the stock and rolling equipment, state of the roads, weather, wagon loads, etc. 20 to 30 miles per day for empty wagons is, in the U. S., about the best that can ordinarily be expected, and for loaded wagons, 15 to 22 miles. Wagon trains do not usually halt for rest, but roll along to their destination. If the trip is very long or fatiguing, they may halt, for several hours, unhitch and feed, and then resume. They do not ordinarily halt for hourly rests, as do the troops. The speed of wagon trains usually averages about 2 mi. per hour on all kinds of roads. On good stretches of road it may reach 2½ miles, rarely better. Auto trucks will average 5 to 10 miles per hour, depending on roads and other conditions.

The amount of supplies that may be obtained from a given locality depends on a number of factors; whether the community is agricultural or otherwise, and if agricultural what are the ruling crops; the transportation facilities, season of the year, etc. Rural communities are usually well stocked with food supplies, especially in the fall. Of forage especially there will usually be large supplies. Cities and towns habitually maintain a reserve in their store-houses. This reserve is more concentrated, and of greater variety, than the rural reserves.

It is not the policy of the American government in the early stages of a war to strip a locality too closely of its supplies, particularly in friendly territory, and this is also forbidden by the 1907 Hague Convention. But in case of necessity the army must be supplied at any cost. It may be said as a rough rule that a town of 10,000 inhabitants has sufficient reserves of food always on hand to supply a force of 20,000 men for one day without great embarrassment to the population, provided the commercial transportation facilities be not paralyzed. Col. Hazenkampf in his work entitled “The supply of an army in time of war,” says: “From the experiences of former wars we have come to the following general conclusions:

1st. If the population of a given point or locality be equal to the number of troops, it can supply them for a period of 4, but not more than 6 days.

2nd. If the number of troops be half the number of the population, they can be maintained at the expense of the latter for 1 to 2 weeks.

3rd. Lastly, the number of troops being a quarter of the number of inhabitants, they can be supplied for a space of 3 or 4 weeks.”

These figures are too great for application to the American service. The food thus obtained locally is not, of course, the balanced regulation ration. In campaign, soldiers must take things as they come and make the best of the food they get from day to day.

_Some Supply Data._

The following data will be useful in connection with the subject of supply:

Standard gauge box freight cars in the U. S. have capacities varying from 20 to 50 tons. Their inside cargo space is about 8 ft. X 8 ft. and the length runs from 30 to 40 feet, or more.

Box cars for narrow gauge roads are similar in construction to, but of smaller dimensions than those for a standard gauge road; they have carrying capacities up to 15 tons.

Flat cars and gondolas have about the same carrying capacities as box cars. An average car has a capacity of 80,000 lbs. They are designed to carry heavy and bulky articles that will not be injured by exposure to the weather.

The supplies of an army are bulkier than much of commercial freight. The cars will not always be carefully loaded, nor their full capacities realized. Allowances should be made for these facts in estimating the number of cars required.

Day coaches accommodate comfortably 40 to 50 men, but 60 to 65 can be crowded into them for short hauls.

Sleepers carry 3 men to a section, and have 12, 14 or 16 sections.

Wounded should not be packed in too closely; ordinarily each will require an entire berth. A large box car will accommodate 20 to 25 recumbent wounded.

Ordinary stock cars carry 16 to 20 animals. For short hauls they will carry 25. They are slatted but have no stalls. They are arranged for feeding hay but not grain or water. Animals should be unloaded and watered once in 24 or certainly 36 hours. Palace stock cars carry 16 to 24 animals. They are fitted with stalls and with arrangements for feeding and watering en route. Care is necessary to see that the water tanks are filled and tight.

In railroad movements a guard and unloading detail should be arranged for when necessary. The details if desired may best be sent with the leading train.

The table following gives the weights and cubic contents of various rations for men and animals, and the capacities of carriers for careful loading. If the loading is not carefully done the stated capacities will not be realized and allowance should generally be made for this. From this table the number of carriers of any class required for a stated number of rations may be computed.

Thus assuming a division at approximately 20,000 men and 8,000 animals, one day’s reserve rations will require 15 wagons, 1 day’s hay for animals 46 wagons, 1 day’s grain for animals (250 rations to a wagon), 32 wagons. A 40,000 lb. box car, fully loaded, is equivalent to about 15 wagons; for ordinary loading (20% waste) about 12 wagons. In any case the actual capacities of the cars available should be ascertained, and 20% excess allowed for inefficiency of loading.

Beef is often transported on the hoof, 16 to 20 cattle to a car. For fresh vegetables the required cubic capacity is computed.

ALLOWANCE OF FORAGE, AND APPROXIMATE WEIGHTS AND MEASURES OF FORAGE AND SUBSISTENCE.

LEGEND:
A = Gross weight of one ration (lbs.).
B = Number of rations to a 40,000 lb. box car (36 by 8 by 8).
C = Part of box car required for one ration.
D = Number of rations to an Army wagon (2,765 lbs.).
E= Number of rations to an auto truck (3,000 lbs.).
F= Cubic feet to one ration.
G = Number of rations to a cubic foot.
H = Number of rations to a ship’s ton (40 cubic feet).
I = Part of a ship’s ton required for one ration.

----------+----+------+-------+-----+-----+-----+------+---------+------
Kind of | A | B | C | D | E | F | G | H | I
ration. | | | | | | | | |
----------+----+------+-------+-----+-----+-----+------+---------+------
Forage: | | | | | | | | |
Oats-- | | | | | | | | |
Horse |12 | 3,333|.0003 | 230| 250|.39 | 2.564|102.6 |.00974
Mule | 9 | 4,444|.000225| 300| 333|.2925| 3.42 |136.75 |.0074
Hay-- | | | | | | | | |
Horse |14 | 1,571|.000636| 175| 175|1.12 | .893| 69.69[9]|.0143
Mule |14 | 1,571|.000636| 175| 175|1.12 | .893| 69.69 |.0143
Barley--| | | | | | | | |
Horse |12 | 3,333|.0003 | 230| 250|.312 | 3.205|128.2 |.0078
Mule | 9 | 4,444|.000225| 300| 333|.234 | 4.274|170.9 |.00585
Corn-- | | | | | | | | |
Horse |12 | 3,333|.0003 | 230| 250|.27 | 3.703|148.15 |.00675
Mule | 9 | 4,444|.000225| 300| 333|.2025| 4.94 |197.53 |.00511
Bran-- | | | | | | | | |
Horse |12 | 2,500|.0004 | 230| 250|.72 | 1.39 | 55.55 |.018
Mule | 9 | 3,333|.0003 | 300| 333|.54 | 1.85 | 74.07 |.0135
Subsistence:| | | | | | | | |
Garrison| 4.9| 8,226|.000122| 565| 600|.149 | 6.73 |269 |.0037
Travel | 4.1| 9,818|.000102| 675| 750|.129 | 7.76 |311 |.0032
Field | 3.0|13,428|.000075| 920|1,000|.111 | 9.04 |362 |.0028
Reserve | 2.0|20,142|.00005 |1,380|1,500|.074 |13.56 |543 |.0019
----------+----+------+-------+-----+-----+-----+------+---------+------

[Footnote 9: Compressed to 82 cubic feet per ton (2,000 pounds), the minimum density for oversea shipments.]

The supply data and discussion in this chapter are to be regarded as tentative and serving only for purposes of illustration. The organization of the supply service as well as that of the tactical units, varies from time to time and the latest tables of organization issued by the War Dept, should be consulted. Moreover, it is certain that any prescribed organization will be varied to a considerable degree in actual campaign. So many conditions enter supply problems that each must be solved in the light of those conditions. The foregoing discussion is intended only to indicate the general nature of the problem and the manner in which its solution should be approached.