The microscope and its revelations (1901) (14580483748)

Identifier: microscopeitsrev00carp (find matches)
Title: The microscope and its revelations
Year: 1901 (1900s)
Authors: Carpenter, William Benjamin, 1813-1885 Dallinger, W. H. (William Henry), 1842-1909
Subjects: Microscopy Microscopes Natural history
Publisher: Philadelphia, P. Blackiston's Sons and Co.
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library



Text Appearing Before Image:
FIG. o97.—Freezing apparatus for the Thoma microtome. The freezing is effected by ether-spray. A specially favourableeffect is obtained if the cylinder <j is mica and not glass. A layer ofwater freezes in from thirty to thirty-five seconds. An arrangement of the Thoma for cutting lury objects has alsobeen devised which is illustrated in fig. 398. The knife is to be placed considerably higher in front thanbehind, in order to lessen the pressure on the objects In order tosatisfy all demands, the knife-rest is adjustable. The knife is so arranged that the whole length of blade can beused, and then the screw c is fairly tightly screwed down. As strong-knives, even of a length of 36 cm., easily give, a knife-support hasbeen constructed ; this is fastened by 1 he screw cf to the carrier.The support is arranged parallel with the back of the knife M ; ifthe extremity n be slightly pressed backwards, so that it touches the H H 2
Text Appearing After Image:
THE ROCKINO MICROTOME 469 knife, it i.s then fixed in this position by the screw o (scarcely evidentin the illustration). This done, the spirit-vessel fy> can be arranged in a position\vhich will not interfere with the free movement of the knife. Inorder that a stream of spirit may follow the knife over the object,the following- arrangement is adopted. The spirit-vessel S/» turnsround an axis 011 the column // ; to it is joined the arm L, whichcarries in front the fine tube r (connected with tt), and also the rod/>; the latter is movable perpendicularly, and to its lower end abridge or grip with two small rollers i and / is fastened. The rod)> is so placed that on each side of the metal strip b, screwed on tothe knife-support, there is one of the rollers. By the adjusting-screws Stf, the whole apparatus is so arranged that, when the knife-carrier is in motion, no other friction occurs than that of the rollerson the stiip b b b. The vessel is filled by screwing off the head Z