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
History of same-sex marriage in the United States and required the state to recognize same-sex marriages. On November 12, 2008, the first marriage licenses to same-sex couples were issued and the following year, the state enacted gender-neutral marriage legislation. In August and September, the national political parties addressed same-sex marriage in their party platforms. The Democratic National Convention adopted a platform that "oppose[s]the Defense of Marriage Act and all attempts to use this issue to divide us" and suggested support for same-sex marriage: "We support the full inclusion of all families, including same-sex couples, in the life of our nation, and support equal responsibility, benefits, and protections." The