The society presents a Guy medal (in memory of Dr. W. A. Guy) to the authors of valuable papers or to others who have promoted its work, and a Howard medal (in memory of the great philanthropist) to the author of the best essay on a prescribed subject, generally having relation to the public health. It has accumulated a fine library of about 40,000 volumes of a special character, containing the statistical publications of all civilised countries. It has conducted some special enquiries--as into medical charities, the production and consumption of meat and milk, and the farm school system of the Continent--upon which it has published reports. Among recent developments of statistical method in which the society has taken part may be mentioned the use of index-numbers for affording a standard of comparison between statistics of different years, and a means of correction of errors that would otherwise arise; and the increasing use of the higher mathematical analysis in determining the probabilities of error and defining the curves of frequency in statistical observations. Professor Edgeworth, Messrs. Bowley, Yule, Hooker, and others, have made contributions to the _Journal_ of the society on these matters. In 1844 an Ethnological Society was established, under the presidency of Sir Charles Malcolm. Dr. Richard King, the founder, became its secretary. In 1846 Dr. J. C. Prichard became president, and he and Dr. King fulfilled respectively the same functions in an ethnological sub-section of the section of zoology of the British Association, which then met for the first time. In Prichard's first anniversary address to the society, he defines ethnology as "the history of human races or of the various tribes of men who constitute the population of the world. It comprehends all that can be learned as to their origin and relations to each other." Prichard died in 1848, and Sir C. Malcolm resumed the presidency, which he held until his death on November 12, 1851. In that year ethnology was transferred from the zoological to the geographical section of the British Association. Sir B. C. Brodie became the next president of the society. He retired in 1854, and was succeeded by Sir James Clark. The fourth and last volume of the first series of the society's _Journal_ was published in 1856, and a series of _Transactions_ begun in 1861. At that time Mr. John Crawfurd was president of the society, and he retained the office until his death in 1868, when he was succeeded by Professor Huxley.