Concluding remarks

I think you will all agree we have had a most interesting set of papers and discussion arising from them. Certainly this discussion will mark a definite stage in our knowledge of the water substance. It is also evident that very much more work requires to be done, but we are now much clearer as to what is really needed. For instance, Dame Kathleen Lonsdale pointed out very clearly, we really require a proper study of the thermal expansion of ice in different directions right down to as low a temperature as we can reach in order to clear up, among other things, the discrepancy between the macroscopic and the X-ray coefficients of expansion in the different directions. Such a detailed study should enable us to check the very ingenious hypothesis of Professor Frank on the reasons for the much lower transformation temperature of cubic than hexagonal ice.