The following was extracted from the Tolles catalog:
TOLLES'S LARGE MICROSCOPE. B.
This instrument is
intended to meet the wants of the highest scientific
investigation; to attain everything that the
microscope can accomplish, without sparing the cost,
and to permit the use of all the modern accessory
apparatus. Like all of Tolles's' microscopes, it is
constructed on the curved arm (Jackson ) model, which
Dr. W. B. Carpenter, in his elaborate work on "The
Microscope", fourth edition, 1868, preferred over
all other models; and in 1870, at a meeting of the
Royal Microscopical Society, of London, still more
emphatically approved in special communication,
giving his reasons for thus in endorsing it. The
instrument is eighteen inches high, weighs about
fourteen lbs., thus giving a stability and freedom
from tremor that cannot be obtained with stands of
little weight. It is of simple construction, with
fewer screws and pieces than any other first-class
microscope. The curved arm is supported on a steel
arbor between two strong brass pillars, made for
durability, and not liable to get out of order, and
provided with a method of compensation for wear. The
arm is easily clamped and held in any position. and
is readily removable. Has rack and pinion for coarse,
and micrometer screw for fine adjustment for focus;
graduated draw tube; sub-stage with rack and pinion,
and centring screws for accessory apparatus; plain
and concave mirrors, on double. jointed arm, Tolles's
thin stage, admitting light of great obliquity, with
rectangular movements by screw and rack and pinion,
and rotation on the optical axis of about 325 degrees
that is essentially necessary. Price, $225.
N.B. A newly devised
mechanical stage, with rectangular movements
throughout one inch of field, with rotation 360
degrees in the optical axis. Price $200.
The above accessory
is designed to attach to the bar holding the mirror
while the other end has a fitting with a "Society
Screw" which will hold an objective, but what is
the function of this apparatus? Might it have held
a prism to serve as an alternate for the
mirror?
Among the accessories associated with this microscope
are seven Tolles objectives with focal lengths of 1/2, 1/3, two 1/6 (135°
and 180° aperture angle, respectively), 1/8, 1/10, and 1/16 inches.
Another example of the B Model microscope is in the Havard collection.
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 soon
afterwards 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 fronts one 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 an additional
discussion of the life and work of Robert B. Tolles
(1824-1883), see Three American Microscope
Builders published by the American
Optical Company 1945. Also see the essay:
The Aperture War-Research and
Notes by Jim Solliday and the
article Robert B. Tolles and the
Angular Aperture Question (Proceedings
of the American Society of Microscopists, Vol. 6,
(1884), pp. 5-39)
