The Administration, too, of improvised units always leaves much to be desired. The Administrative Services of each portion may be permanent and adequate, but additional ones will be required for the new Unit, as well as improvised Head-Quarters. MacMahon’s failure at Wörth was partly due to his having to command a detached Army with only the Staff of his own Army Corps. IMPORTANCE OF PRESERVING ORIGINAL ORGANIZATION The organization of a force regulates the conditions of its command and administration, and should be altered during the war only if it be absolutely necessary to do so. Any alteration interrupts the accustomed channel for Orders, necessitates changes in Commanders and Staff, and disorganizes the system of Supply. An improvised unit, it has already been shown, is never so efficient as a permanent one, and to form one will rob some existing units to provide the new Commander and Staff. Change in organization, therefore, makes control less effective, and tends to confusion in administration, and to general diminution of efficiency in the Force. At the same time, the original organization must not be regarded as immutable, if the Commander-in-Chief considers it necessary to alter it. This is definitely laid down in Field Service Regulations, Part ii., sect. 8, pars. 6 to 10. A redistribution may become imperative for reasons of Strategy or Command, but fewer occasions for this necessity will arise if the original organization has been well thought out, so as to meet all requirements which can be foreseen. In the South African War the organization by Army Corps was given up at the beginning, and has never been revived. But in this connection it may be submitted that the frequent formation of improvised sub-commands for special purposes was responsible for loss of force in their leading, which sometimes entailed failure, as in the case of De Wet’s escape. It is a rule that units should, if possible, be kept intact when forming detachments like Advanced Guards, or those for special operations, which should not be formed out of fragments of several units, like the force defeated at Majuba Hill in 1881. THE ORDRE DE BATAILLE In planning the movements of a force it is desirable to keep the Sub-Commands in the same relative position throughout. Thus, a corps originally on the right of another should not get to the left of it, nor one in rear pass another in front of it. This will avoid useless marching and delays, and confusion in the trains in rear.