Between June 1917 and the opening of the Third Battle of Ypres each tank battalion received six supply tanks, two for each company, but during this battle they did not prove a success on account of the appalling conditions of the ground, the sponsons continually becoming wedged in the shell-holes, which necessitated much digging out to relieve them.

Just prior to the opening of this battle the first of the gun-carrier tanks arrived in France, and was dispatched to Flanders and attached to the XVIIIth Corps for experiment. Later on others followed, until by the end of the year forty-four of these machines had been received.

The idea of the gun-carrier was that of mechanical artillery, the machine being really a mechanical gun mounting capable of carrying a 60-pounder or 6 in. howitzer. Its total shell capacity without the gun was 200 6 in. shells, weighing approximately 10 tons.

Considering the difficulties of the ground very good work was done by the gun-carriers during the Ypres operations, several hundreds of tons of ammunition being carried forward as well as a few 60-pounders.

In September a new method of supply was experimented with; this consisted in towing behind any type of tank three sledges connected with the roof of the machine by a cable. At the battle of Cambrai this method proved a great success, and not only were tank supplies hauled forward but also telegraph cable and bridging material.

During the autumn and winter of 1917 much careful thought had been devoted both in France and England to the question not only of tank supply but of being able to carry forward infantry, particularly machine-gunners, in armoured carrier tanks; the result of this was the design of a large carrier tank known as the Mark IX and the raising of a new unit known as an “Infantry Carrier Company.”

These carrier units were first formed on February 1, 1918. The first two companies consisted mostly of Royal Engineer personnel, and the next three of infantry. The standard of the personnel was very good, about 60 per cent. having already seen service overseas. The 1st and 2nd Companies proceeded to France about the middle of May, the remaining three arriving in June and July.

The organisation of each of these companies was as follows:

A company headquarters and four sections, each section consisting of six Mark IV supply tanks, or tenders, as they were sometimes called. The object of these companies was laid down in Tank Corps Standing Orders as follows:

“The Tank Supply Company is a unit of Brigade Troops for the carriage of supplies, from the point where wheeled vehicles cease, to battalions. The responsibility for maintaining battalion supplies rests with Brigade Headquarters. The duties of the Brigade Supply Officer will in no way be shared by the O.C. Tank Supply Company. The Tank Supply Company will be used as a mobile reserve of supplies under the immediate control of Brigade Headquarters.”

These supply companies were never used for carrying forward infantry, as the Mark IX tank did not materialise until October 1918; they proved, however, of the greatest use during all the tank operations of the last year of the war.