I will tell you exactly what I like about this and it is not the specification. It is that it removes a bet. Every match you have ever played with a normal bottle, you have been quietly gambling that you would not need more than you brought — and on a hot afternoon, in a third set, against someone fitter than you, that is a bet you lose.

Sixty-four ounces. You will not run out. That is the whole product and it is worth more than most features I could list you.

Half a gallon takes the wager off the table.

The insulation is the second half of it, and it is doing something more useful than keeping the water cold as a luxury. A cold drink in the heat is a genuine performance item, not a comfort item — you will drink more of it, and drinking more of it is the actual objective.

An insulated jug is also the difference between water that is still worth drinking at four o'clock and water that has been sitting in a car since noon and now tastes like the inside of a bag. A half-gallon vessel is big enough that it is not really a bottle any more; it is the bench supply, sitting in the shade by your bag, which the small bottle in your hand refills from.

That is how the professionals arrange it and there is no reason you should not.

Pondicherry is the right place for a lesson about supply and confidence, because it is a town built entirely on people arriving from a long way off and deciding to stay. Notre Dame des Anges was finished in 1855 with lime plaster mixed with egg white, which is an act of faith in a recipe.

Raj Nivas faces the park. The old lighthouse on the seafront was first lit in 1836, for the specific benefit of people who were still out there in the dark and needed to know the shore had made arrangements.

The Aayi Mandapam stands white at the centre of Bharathi Park because of a story about a water supply.

Never bet on the weather. Bet on having brought enough.

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