TOLLES'S STUDENT'S MICROSCOPE
15 inches high, weight 6 pounds
This instrument, designed under the advice of several of the Professors of the Medical School of Harvard College and other well-known Microscopists, is of the pattern and size most approved by experts. The base, uprights, and curved arm are of iron, handsomely japanned; on a trunnion joint, made on a new plan to wear well, by which the instrument can be placed in any position, from vertical to horizontal, with a stop to prevent movement
in either direction
beyond these points. It is furnished with a l-inch Eye-Piece, two second-quality Objectives, of about 1 inch and 1/4 inch power, giving about 80 and 350 diameters, a plain Stage with spring clips for holding the object slides, revolving Diaphragm, concave Mirror, with movement to give oblique light; for illumination of opaque objects, the mirror is removed to an upright stand; course adjustment for focus is effected by sliding the compound body which is held in its place by a spring, fine adjustment
by a movable
plate and screw on the stage, which is efficient with high powers. The stand is made with all the care bestowed on his first-class instruments, and proves satisfactory for the use of amateurs, students, and the ordinary work of the medical profession. The workmanship is superior to that of any instruments of the class made in Europe. The form is the Jackson pattern recommended by Dr. W. B. Carpenter as the one least liable to tremor, and is the one most approved by all American microscopists. Price, in an
Black Walnut case, $50. Stand and Case alone $28.
Variations and Additions. - Extra Eye-Pieces, 2 in. 1 1/2 und 3/4. $4 each; a superior Camera Lucida $5; Sub-Stage for Accessory apparatus, $5; a Sliding Stage, giving vertical and horizontal motions by the hand, and adapted for the use of Mathwood Finder, $15. Fine adjustment by lever and micrometer screw, $16. Rack and Pinion for coarse adjustment, $12, drawtube, $4. Plain Mirror, $3. Thin glass stage to rotate on the optical axis, $10. The
stand in all brass,
$10. Any of TolIes’s first quality Objectives may be used on this instrument, and can be added to order at list prices. Packing Boxes for transportation, $1.
The following was extracted from The National Cyclopedia of American Biography, vol. XIII, 1906.
TOLLES. Robert B.,
lensmaker, was born in Winchester, Litchfield co., Conn., about 1825,
son of Elisha and Harriet Tolles. His father was an inventor, but from
lack of funds was unable to develop any of his ideas. The son was
educated in the common district school and passed his boyhood at home
and on his grandfather's farm near by, working to aid in supporting the
family. In 1813 while in Canastota, N. Y., he accidentally visited the
workshop of Charles A. Spencer, and
he entered the service of the celebrated lensmaker as an apprentice.
Under the instruction and guidance of this remarkable man young Tolles
learned the special business in which he displayed such genius. In 1858
he started in business on his own account in Canastota, removing to
Boston, Mass., nine years later, where he organized the Boston Optical
Works. He was affiliated with this company the remainder of his life,
for the first four years as superintendent and thereafter as sole
proprietor. His one aim in
his business was the improvement of the microscope, and his achievements
in this line prove that he was well qualified for the task by his "
great theoretical and practical knowledge of the science of optics,
united with mechanical and inventive genius and marvelous skill of eye
and hand." While still in the service of Mr. Spencer he devised a cover
correction for objectives, and invented and patented a solid eye-piece.
In 1858 he made his first immersion objectives, and objectives with two
to be used as an immersion and the other dry, and in 1866 he obtained a
patent for a stereoscopic binocular eye-piece. He invented many other
devices and appliances for the microscope, as well as some telescopes
remarkable for their short focal length in proportion to the diameter of
object-glass and for their defining and penetrating power. The great
step, however, which placed him, together with Charles A. and Herbert R.
Spencer, at the head of his profession, was the construction in 1873 of
an immersion one-tenth
objective with an aperture greater than that corresponding to infinitely
near 180 degrees in air. It was a three system lens which had an
aperture of more than 110 degrees in balsam, or 1.25 N. A., and which is
said to have produced " a revolution of opinion and practice among
users and makers of microscopes all over the world." At the same time he
also made his first lens of the duplex front formula one-fifth inch
glycerine immersion of 110 degrees balsam angle. On Aug. 10, 1883, he
was elected an
honorary member of the American Society of Microscopists.
Notwithstanding his valuable achievements, the last ten years of his
life were years of suffering and hardship; he worked at his bench when
he should have been in his bed, denying himself all the luxuries and
many of the comforts of life. He greatly suffered from a disease of the
lungs which was contracted at an early age and which caused his death.
During his last illness, he had a microscope brought to his bedside and
there on his deathbed examined and
tested the lenses. Only a few minutes before his death he was occupied
in correcting the degrees of aperture of an imaginary lens and when he
reached 150 degrees, he stopped, turned his head and said faintly,
"Goodbye. He was married in 1853 to Freelove S. Dickey, but was left a
widower a few months later. He died in Boston, Mass. Nov. 17, 1883.
For a discussion of the life and work of Robert B. Tolles see: Three American Microscope Builders published by the American Optical Company 1945.