‎"CROOKES, WILLIAM. - THE FOURTH STATE OF MATTER.‎
‎The Bakerian Lecture. - On Radiant Matter Spectroscopy: The Detection and wide Distributium of Yttrium. Received May 24, - Read May 11, 1883. (+) On Radiant Matter Spectroscopy.- Part II. Samarium. Received May 21, - Read June 18, 1885. (2 Papers).‎

‎(London, Harrison and Sons, 1884 a. 1886). 4to. No wrappers as extracted from ""Philosophical Transactions"" 1883. Vol. 179 - Part II. Pp. 891-918 and 1885. Vol. 176 - Part II. Pp. 691-723 and 1 plate (chromolithographed spectra), many textillustr. of spectra. The plate with small spots in margins.‎

Reference : 42404

‎First appearance of these papers in which Crooles continues his cathode rays experiments with his Crookes tube, obtaining spectra of elements which he regarded as new. His experiments lead him here to his speculative theory of the elements having a common ancestor, a primordial matter.Sir William Crookes (1832-1919) studied at the Royal College of Chemistry , London, and served there as an assistant to Hoffmann. In 1859 he founded the Chemical News and remained its proprietor and editor until his death. he early attracted attentuion by his discovery of the element thallium by spectroscopic methods. he was an active investigator in many fields of physics and contributed greatly to the advance of knowledge by his study of the radiometer and of the electric discharge in rarefied gases.‎