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We define a point-free construction of real exponentiation and logarithms, i.e.\ we construct the maps exp:(0,∞)×R→(0,∞),(x,ζ)↦xζ and log:(1,∞)×(0,∞)→R,(b,y)↦logb(y), and we develop familiar algebraic rules for them. The point-free approach is constructive, and defines the points of a space as models of a geometric theory, rather than as elements of a set - in particular, this allows geometric constructions to be applied to points living in toposes other than Set. Our geometric development includes new lifting and gluing techniques in point-free topology, which highlight how properties of Q determine properties of real exponentiation. This work is motivated by our broader research programme of developing a version of adelic geometry via topos theory. In particular, we wish to construct the classifying topos of places of Q, which will provide a geometric perspective into the subtle relationship between R and Qp, a question of longstanding number-theoretic interest.