Each of the five Phase I house-bases were designed to double-up as dinner halls. Rather than have one kitchen in each base, the arrangement of the bases allowed for large kitchens, slotted between the buildings, to serve more than one base.
The Large Kitchen caters for Osborne, Hatfield and the Old 6th Form Base. A consequence of this is that the building completely blocks off any route through the centre of the Upper School campus. The Small Kitchen only serves two bases: Segrave and Athorpe. This allows a path between Segrave and Osborne. The kitchens could theoretically have been the other way round (a large kitchen serving Segrave, Osborne and Athorpe), freeing up the centre of campus, but this would have isolated Segrave to some degree, and by association Osborne (which would have to be reversed).
The Large Kitchen was equipped to serve 850 meals, while the Small Kitchen was for 550. You don't have to be the Morg to know that that means that Hatfied, Osborne and the 6th Form would be averaging 283.33 servings while Athorpe and Segrave would only get 275 a piece. It was probably for this reason that Athorpe was the one house to get out of a second dinner sitting when the High School first opened.
Before Upper School arrived, dinners were served in the 'Lower School' halls. It's possible I'm wrong, but the only sensible location for the Lower School Kitchens is the area to the south of the centre quad, backing onto the chimney, and adjoining the two halls. After Phase I, these kitchens were redundant. The first suggestion for their future, in 1963, was that they should be turned into changing rooms. Evidently this didn't happen, as by 1965 a scullery was proposed instead, suggesting that the kitchens were still pretty-much plumbed in. Whatever happened, by the '80s they'd become a pair of offices: the left for the A/V Department, and the right (eventually) for Business Studies (perhaps RE before that).
By the 1990s, the Small Kitchen between Athorpe and Segrave had fallen out of use. Osborne and the 6th Form were the dinner halls in the early '90s, with Hatfield replacing the latter c.1995. There were no longer second sittings either, so the school had gone from effectively nine sittings in 1963 to two in 1993. The population of the school had reduced by 160 in that time, but that only accounts for about one sitting. The rest of the wastage must have come from sandwiches and trips up the street. I consider myself typical of a general trend in the '90s in that I started with school dinners, before realising that all the good stuff (like Tom-Toms (turkey balls stuffed with tomato sauce)) went stupidly quickly and was gone by the time you were served. Then I went up the street, varying chip butties from the Fish Net with pork sandwiches or steak pies from Armstrong's Game Butchers, until my arteries could take no more and I retired to Hatfield with my friends and my sandwich box.
Having lain dormant for a while, the Small Kitchens were eventually ripped out c.1993, and converted into History and English classrooms. This procedure was by no means simple, and required an airlock tent on account of the asbestos being disturbed. Segrave pupils wrecked their lungs as much by holding their breath for too long as by anything else.
The kitchens were partitioned as three rooms (or so I recall), one to the east and two to the west, and were the first step in an attempted escape from the Terrapins by History and English that might almost incriminate them in the Lower School fire. The fire actually brought an end to History and English's occupation not just of the Terrapins but also of the Small Kitchen, and once they'd moved out at the turn of the century, a further stage of partitioning ensued. This produced five rather cosy little rooms (LS 1 & 2 down the east side, with 3-5 running back up the west), the small size no doubt considered ideal for remedial tuition. LS stands for Learning Support, and the Small Kitchen is now the Learning Support Centre.
Despite losing its kitchen, Segrave has, since the turn of the millennium, joined the ranks of Hatfield and Osborne as a dining hall, suggesting a resurgence in school dinners. This means though that food has to be trolleyed into Segrave at lunchtimes. Perhaps to aid this transport, Segrave has recently received an extension to its hall-space: a sort of big porch thing that extends into the grass-area to the south of the base.
A Staff Kitchen upstairs in the Admin Block completes the catalogue of kitchens on campus. This consists of a woman serving sandwiches, and a coffee machine. It is a small concern, and like Segrave it may simply be an outlet rather than a kitchen in its own right.
Until the '90s, and maybe still to this day, the Large Kitchen catered not only for dinners, but also for light snacks, and operated a tuck-shop affair at its main door (between Hatfield and Osborne) at first break. This sold little bottles (later cartons) of milk, sundry bought-in confectionary and the kitchen's own specialty: flapjacks. A Large Kitchen flapjack set you back something like 10p, and would still be warm. It was a scrummage to get served, but worth it in the end to feel that cosy grease in your palm and the smell of cooked oats. Flapjack quality of course varied, and it was often best to wait and see what the output was like before you dived into the mêlée yourself. The biggest risk was not so much physical injury as getting covered in milk, actually.
Housebase tuck shops were often likewise something of a physical challenge. Especially Osborne's during the period when it operated from a cupboard. Osborne had a bar area, but selling sweets from there would obviously be lacking in challenge, and against the Osborne ethic. Hatfield had the best tuck shop for a good while in the early '90s, taking over the glass-walled study, and even getting a countered stable-door from which to serve. The glass wall meant for better display of goods, which probably helped.
Hatfield's tuck-shop died around the same time that it took on dining duties, and Segrave capitalised on this by reviving its own, long dormant, tuck shop. This was run from the middle office (used as a prefect common-room) which had long since been equipped with a serving hatch and a sign saying "Tuck Shop" or something more originial. Athorpe also had a resurgence in the mid-'90s, and both countered the threat of vending machines by concentrating more on jellied penny sweets for 10p mixes and the likes.
The vending machines entered the bases in the mid-'90s, taking up the space formerly occupied by pinball machines, and taking out the chaos of the tuck shops. More lascivious boys welcomed their advent for the chance to see girls' bottoms displayed in all their pertness; a general side-effect of the necessary bending down to retrieve tasty goodies.
It should be said that the vending machines were nothing new. The Swimming Pool had had a drinks machine since at least the '80s, and plans for three Auto Bar vending machines to be installed in the school had been made for September 1966.