Message 14592 of 14609 From: "mervhob" Date: Mon Feb 16, 2004 12:01 am Subject: Re: Rene request for Data -Diatom Pics Rene, Quoting E.M. Nelson, 1900, the first water immersion was brought to London in 1855 by Prof. Amici. However, its aperture was no greater than that of the high drys of the time - the P&L 1/16" had an NA of 0.99(175deg). This was followed by water immersions by Hartnack in 1862 - these were stated to be inferior to the P&L 1/25" dry with an NA very close to 1.0(!). This could resolve Norbert's 15th band, 90,078 lpi, or 281nm. In 1869 P&L produced their first W.I. objective, 1/16" which Col. Woodward used to resolve the 19th band, 112597 lpi, or 225nm. This was beaten in 1872 by Tolles W.I. with a duplex front, which Woodward said beat all other objectives that he had in his collection. The higher aperture W.I. objectives did not start to appear until the 1870s, as it began to be appreciated, due to Tolles, that the working aperture could be improved by this means. This started the infamous 'Battle of the Apertures', in which Wenham refused to accept that improvement was possible. So it is extremely unlikely that Sollit and Harrison used a W.I. in 1862, in fact, we know that they did not - Carpenter states, regarding the ability to see stria on Amphipleura Pellucida, and the doubts that had been expressed by Hendry and others, he himself is convinced, 'having himself seen regular, distinct, and unmistakable stria in this Diatom - through the kindness of Mr. Lobb who has shown him this object with a 1/8" objective on Messrs Powell and Lealand's large microscope with an achromatic condenser of 170deg.' I am inclined to take Carpenter's word for this - as my friend Ted Brain points out - 'Well, they just didn't know any better!' Cheers, Merv Message 14599 of 14607 From: James Solliday Date: Mon Feb 16, 2004 6:28 am Subject: History of the Immersion objective: Jim All you every wanted to know about Immersion Objectives. The story actually starts quite early when in 1678, Hooke gave his presentation, "Lectures and Collections" which was published that same year in his "Microscopium". Hooke was the first to suggest the technique of Immersion. He writes: "that if you would have a microscope with one single refraction, and consequently capable of the greatest clearness and brightness, spread a little of the fluid to be examined on a glass plate, bring this under one of the globules, and then move it gently upward till the fluid touches and adheres to the globule". By 1812, Sir D. Brewster suggested immersion of the objective into the liquid medium. Amazingly about that same time Amici began addressing the problem of chromatic aberration (Woodruff, 1939). By 1840, the first immersion lenses were made by Pro. Amici. According to Mayall they were designed to be used with oils having the same refraction as glass, homogeneous-immersion (Mayall, pp.1119) (The Northern Microscopist, Vol.2, 82/307). This was not done with the conception of increasing the apertures that revelation was left to Tolles. Amici's work was intended to get more correction of the aberrations. However, the use of oil on expensive slides was not readily accepted by the public, Amici gave up the oil system and adopted water as the immersion fluid (Mayall, pp.1119). In 1853, Prof. Amici of Modena constructed his first water immersion objective (W.G, Hartley, 1993). At the 1855 Paris Exposition, Amici introduced his water immersion objective. Nachet Sr. and Hartnack were inspired to work out systems of their own (Mayall). By 1858, Tolles made his first immersion objectives, with water, which had two frontals. Tolles constructed objectives with two exchangeable front elements, one for dry work and the other for water immersion (Three American Microscope Builders, pp.38). In a meeting of the Boston Society of Natural History (1867), Charles Stodder demonstrated a Tolles 1/10th objective, both dry and wet (Warner, 1997). In August 1873, he made his famous homog. immersion 1/10th (AMMJ,1884, pp.168). In 1859, Edmund Hartnack first exhibited his water immersion objectives (W.G, Hartley, 1993, pp.36/328). He also added the correction collar to the water-immersion lens for the first time. Hartnack sold 400 of these lenses over the course of the next five years. By 1860, the following makers were producing (water) immersion objectives. Nachet, Bruno Hasert in Eisenach (said to be as good as Hartnack's), C. Kellner in Wetzlar, G&S Merz of Munich, Friedrich Adolph Nobert in Pomerania and Hugo Schroder In Hamburg. In that same year, Pieter Harting compared a P&L 1/25th dry objective with Hartnack's most powerful (water) immersion lens and found in favor of the P&L. In 1862, Hartnack displayed his immersion objectives at the London, International Exhibition. That same year Prazmowski joined Hartnack (Paris), together they made substantial progress in the water immersion objectives, thanks to Prazmowski's combination of theory and practical skills. The result was that by the 1867 PARIS exposition, Hartnack's lenses were judged the best (Mayall, pp.1119). Prazmowski was the former director of the Observatory of Warsaw (Varsovie). In 1877 he continued the business of Mr. Hartnack (Paris) who had been the successor to the celebrated factory of Oberhaeuser (Trutat, Traité Élémentaire du Microscope 1883, pp.131). In 1864, Pro. Hamilton L. Smith reported that "Messrs. Wales & Co. intend to supply with their higher objectives an extra front for immersion in water", this was a reference to William Wales. His best known objective was a 1/30th inch made for the Army Medical Museum that Woodward used later to photograph Amphipleura pellucida (RMS, June,1964, pp.125). In 1865, Powell & Lealand were the first in England to make a water immersion lens (W. Hartley, 1993, pp.31/36). Beale said that Powell made for him a 1/25" immersion after the lead of Hartnack. See 1869. On Oct. 15th, 1865, Powell delivered a 1/50" immersion objective to Lionel S. Beale (W.G. Hartley, 1993, pp.31). In 1868 Powell undertook additional experiments with immersion systems after Mayall showed him examples (objectives) produced by Hartnack (Mayall, pp.1119). By 1869 Powell's immersion lenses were considered the best in the field. He had made a few tenuous immersion lenses for Beale in 1865, which was some time before he offered them to the general public. In 1867, Gundlach showed his new glycerin immersion objectives at the Exposition Universelle, Paris (1867), claiming "the first instance of the intentional construction of objectives for use with an immersion fluid of higher refractive index than water"(RMS, June,1964/124). Also at the 1867 PARIS Exposition, Hartnack exhibited his improved water immersion objectives (Mayall). The exhibit of Hartnack & Prazmowski surpassed all other entries for his new immersion lenses. That year, Hartnack produced a water-immersion objective of 1/12th inch (No.9) & 1/21inch (No.12). In 1867, Tolles made immersion lenses for glycerin as well, the 1/16th inch immersion which resolved Nobert's 19th band, possibly for the first time. Witnesses: Mr. R. C. Greenleaf and C. Stodder, Boston (AMMJ,1893, pp.303). By 1870, Thomas Ross (at the suggestion of H. Van Heurck) began making water immersion objectives. His 1/12th was well received but very expensive. In 1871, Tolles demonstrated his homogeneous immersion objective using Canada balsam as a medium. At the death of Mr. Tolles the editor of The Microscope, Mr. Stowell received an account of the life of Tolles from Mr. C. Stodder, Boston, Tolles business partner. Concerning the Tolles homogeneous objectives he records, "This he demonstrated in 1871, but owing to the fact that at that time Canada balsam was the only fluid known to possess the same refractive index as crown glass, his discovery remained useless until 1877, when Prof. Abbe discovered a fluid which was practical for such a purpose." (The Microscope, 1884, No.1, pp.5). However, attention was afforded Mr. Tolles on this concept in 1873, with the production of his 1/10th immersion. In 1871, A public debate began between Tolles and Wenham over the question of the aperture of immersion objectives. The debate actually began with a disagreement between Dr. Pigott and Wenham, drawing Tolles in with a challenge put out by Wenham. Hartley says that in 1871, Zeiss produced their first water immersion objective. However, it is certain that in 1872, Zeiss introduced Abbe's water-immersion objectives. The Zeiss catalogue offered 3 water immersion objectives, all claiming an angular aperture of 180º. Described as follows: a 3mm, a 1.7mm and a 1mm, all with an N.A. of 1.0. The No.3 (1.mm) came with a correction collar. In August of 1873, Robert Tolles made a 1/10th inch objective for homogeneous immersion in Balsam, having an aperture of 110 degrees or 1.25 n.a. (Three American Microscope Builders, 1945)(AMMJ, 1884, pp.168) and being a three-system lens. This represents the first publicly recognized true homogeneous immersion system for the microscope (Bradbury, 1969) (JQMC, V.32, pp.294). The same month he made his first lens of the duplex front formula, a 1/5th glycerin immersion of 110° balsam angle (n.a. 1.27) (TAMB/38). Both passed into the possession of the Army Medical Museum at Washington, both used in softened balsam (AMMJ,1884, pp.168). In 1874 his formula and objective were sent to England for inspection and submission in the Journal of the RMS. Earlier in 1873 he also made his 1/5th at N.A. 1.27 (duplex glycerine) and 1/10th at N.A. 1.27 (TAMB/38). This was partly in response to Wenham's denial of the ability of immersion to effect an angular aperture greater then 180° in air (RMS, June,1964, pp.120). Finally, by August of 1877, Zeiss produced Abbe's oil immersion objectives, which became known as "homogeneous" immersion (Innovation, No.1, 1996). Mayall says the date was 1878. However, a bit latter in 1879, Abbe published his paper on Methods for Improving Spherical Correction in the RMS Journal (June). He describes the fluid lenses used in his experiments (1873). He also states that " homogeneous immersion system admits of a useful increase of aperture closely approaching the ultimate limit which is imposed by the optical qualities of the materials available" (RMS,1879, pp.824). As for the use to which these new objective were applied, in 1882, Dr. Robert Koch described tuberculosis (tubercle bacillus). He used a Zeiss oil objectives & Abbe's condenser. Koch met with Abbe and suggested that he develop an achromatic condenser for use in photomicrography. In 1904 the firm of Zeiss presented Dr. Koch with their 10,000th homogeneous 1/12 oil immersion objective. Koch had enthusiastically attributed part of his success to the immersion lenses of Abbe (Zeiss) (Innovation, No.1, 96). Sincerely, Jim Solliday (MSSC).