Graham's law has come to denote an important class of finely divided materials. Around the time Graham did his work, the concept of molecular weight was being established largely through the measurements of gases. Daniel Bernoulli suggested in 1738 in his book Hydrodynamica that heat increases in proportion to the velocity, and thus kinetic energy, of gas particles. Italian physicist Amedeo Avogadro also suggested in 1811 that equal volumes of different gases contain equal numbers of molecules. Thus, the relative molecular weights of two gases are equal to the ratio of weights of equal volumes of the gases. Avogadro's insight together with
Recognition of same-sex unions in Estonia of same-sex marriages or partnerships". On January 4, 2006, five Estonian NGOs supporting LGBT rights issued a press release asking for the Government to draft a new partnership law to give same-sex couples equal rights with opposite-sex couples. On the other hand, a number of conservative politicians claimed that Estonia was not yet ready for same-sex marriage, and that there was no need to create a separate law on same-sex unions since existing laws already implied the protection of some of these unions, despite not mentioning same-sex unions explicitly. Väino Linde, the chief of the Constitution Commission of the Riigikogu