THE MILITARY AND THE RAILWAYS. -- An order has just been issued from the War-office, intimating that arrangements have been entered into by government with the London and Birmingham, Great Western, Brighton, Dover, Grand Junction, North Midland, Midland Counties, Northern and Eastern, Eastern Counties, Birmingham and Derby, Manchester and Birmingham, Birmingham and Gloucester, Manchester and Leeds, York and North Midland, Lancaster and Preston, Newcastle and Carlisle, and Great North of England Railway Companies, for the conveyance of horses of field and staff officers and infantry, when proceeding by route, with regiments and detachments, on railways, and likewise for the conveyance of sick horses of cavalry regiments.  The rates of conveyance are fixed as follow: -- For any distance not exceeding 50 miles, 4d. per mile for each horse; for beyond 50 and not exceeding 100 miles, 3d.  The route, or order, of the commanding officer of the regiment or detachment is to be produced at the railway station, as the authority for the conveyance of the horses, and the written appointment of the principle veterinary surgeon, in regard to the sick horses,is to be annexed to the charge of the public account for such conveyance.  The regulation will have effect from the commencement of this year.