Hamilton Lanphere Smith (1818-1903).
   Smith attended Yale, and beginning in the summer of 1838, with 
Ebenezer Porter Mason & other classmates, built a 12 inch Herschelian 
telescope of 14 feet focal length, at the time the largest telescope in 
the U.S.  Smith graduated from Yale in 1839, and took the telescope to 
Ohio City, Ohio, where he remounted it, 
After this, the fate of the telescope is not documented in the known 
references.
Smith went on to a career of teaching at Hobart College, Geneva, N.Y.   
He is reported to have been the editor / publisher of Annals of Science 
for two years 1853-1854.
   Following are excerpts & synposes of his published works:
---------
Smith, Hamilton L. Reflecting Telescopes. Annals of Science 1 (1853) 
104-105, 117-118, 127-128, 141-142, 188-189, 200-201.  (synopsis)
   "Mr. Sage, of New York, and Mr. Roach, optician, Nassau Street, 
N.Y., have each produced telescopes upon the dialytic principle, 
proposed by Mr. Rogers, and subsequently carried to great perfection by 
Plossel of Vienna, which perform quite well.  I have made two 
telescopes upon this plan, the correcting flint being placed half way 
down the tube, and consequently but half the diameter of the object 
glass…correction for color can be made by properly adjusting the 
distance of the corrector from the single object glass, and a llimited 
correction for spherical aberration by varying the distance between the 
gtwo glasses of the corrector.  It was with an instument of this kind I 
made the observations upon De Vico's comet, which I rediscovered Sept. 
10th, 1842." (p104)
   "…the mysteries of casting, grinding and polishing specula for 
reflecting telescopes…having experienced all the difficulties and 
vexations…In connection with the late lamented Ebenezer Porter Mason, 
at New Haven, I spent many delightful hours over the pages of 
Kitchiner, Edwards, and Mudge…"
   "…the Herschelian…is only superior to the Newtonian from its greater 
simplicity; when, however, as is the case with Mr. Lassell's powerful 
reflectors, a prism is employed for the Newtonian, instead of a 
metallic reflector, there is not much difference in the amount of light
   "I once made a Newtonian reflector of 3 1/2 inches aperture that 
would show, during a strong twilight, the companion of Polaris, and 
separate quite easily the quadruple star, Epsilon Lyrae."
 …"The cheapest, and perhaps upon the whole, the best form of stand for 
a Herschelian telescope, is that invented by Mr. Holcombe, whose 
reflectors are well known in this country, and are not surpassed for 
exquisite finish and figure by the best European instruments.  Mr. 
Holcombe, we believe, uses the elliptical tool…and finishes all his 
mirrors by hand, even when twelve inches in diameter.
   (Detailed description of casting, grinding, and polishing a speculum 
mirror.)
--------

English Mechanic 17 (July 4, 1873) p402. (quoted in entirety) 
   Professor Hamilton L. Smith, of Hobart College, Geneva, N.Y., 
suggests the use of iron or bell metal specula coated with nickel, for 
reflecting telescopes.  He says: "I ground and prepared a bell metal 
speculum, which I coated with nickel, and this, when polished, proved 
to be more reflective (at least I thought so) than speculum metal.  The 
two objects which I sought were, first, to have a polished surface 
unattackable by sulphuretted hydrogen (this, for example, is not 
injured by packing with lucifer matches), and secondly, for large 
specula, doing the most of the work by the turning tool and lathe.  I 
really think a large, say three feet, mirror coated with nickel, but of 
cast iron, and finished mostly in the lathe, while it would not cost 
the tenth of a similar sized one of speculum metal, would be almost 
equal to one of silvered glass the same size, and vastly more enduring 
as to polish."
---------

English Mechanic 21 (March 26, 1875) p35.  Dialytic Telescope.  
(excerpts) 
…I have made four of them, varying from 2 in. aperture to 7 1/2 in.  
The focal length of the last named was 8 3/4 feet (nearly), and its 
performance, upon the whole, quite satisfactory.  The single crown lens 
was 7 1/2 in. clear aperture, and was made from a piece of German 
glass, which appeared, before grinding, to be free from striae, but 
after the instrument was finished, a little group of striae was found 
occupying something less than quarter the area of a marginal ring about 
1 in. in breadth, so that, for fine definition on close double stars or 
the planets, it was necessary to contract the aperture to something 
over 6 in….The curves of the lenses of this telescope were simply 
duplicates of a previous one of half the focal length, and in order to 
test how far the elements for corrections of chromatic and spherical 
aberration existed in the combination itself, no test was made of 
indices of refraction, or dispersive power of any of the glass used; 
and I am quite certain, that any ordinary crown and flint glass will 
give a good result by copying these curves.   The residual errors of 
both chromatic and spherical aberration may be eliminated by simply 
varying the distances between the lenses.  The curves were as follows: 
Single objective crown glass: Radius 76.896 in.; 175.109 in.; most 
convex side outwards.
Corrector:  Plano-convex crown, radius 8.9915 in.   Double concave 
flint: radius 161.14 in.,  9.973 in.
    Flat sides of the corrector together, and the crown next the object 
glass….The corrector was placed about half the focal length of the 
single crown objective down the tube, but as it acted slightly as a 
concave, the prncipal focus of the combination was at a greater 
distance from the corrector, and the focal image was such as would have 
been given by an objective of, say, 10 ft. focal length.  The corrector 
was mounted in a cell sufficiently deep to allow the lenses to be 
placed either in contact, or separated 1/4 of an inch, or more; the 
front lens or convex surface of the crown resting against the usual 
three bearings, and the flint held in place by a ring with three 
bearings opposite to those for the crown; the ring was clamped in place 
by means of three screws moving in slots, to adjust for whatever might 
be the space that separated the lenses, and which, as ultimately 
determined, amounted to two thicknesses of an ordinary visiting card, 
small bits of which were gummed to the lenses, and of course adjusted 
to fall coincident in position with the three bearings of the cell; 
this separation, more or less, of the lenses, was the final correction 
for the spherical aberration, after the chromatic had been corrected.  
The cell of the corrector was screwed into a brass tube about a foot 
long, the diameter of the corrector, somewhat larger than necessary, 
was about 4 in. …the whole was tested for approximate distances 
[spacing]….by means of this apparatus [sliding bench], the approximate 
positions for correction of colour and spherical aberrations were 
determined by testing upon a watch dial, and artificial stars made by 
scratching with a fine point through a smoked surface on tin, and 
placed at a suitable distance. [With a conical telescope tube, the 
corrector was mounted in iron discs that were turned to a diameter such 
that the assembly would wedge at the proper place in the conical tube.  
To secure the corrector in place, a rod was cut to reach from the 
objective to the corrector & screwed into place in the tube.]  …To 
insure centering of corrector, objective, and eyepiece, the latter was 
mounted in a tube of considerable length, and much smaller than the end 
of the telescope tube, so that it could be moved a little laterally as 
might be needed to bring the axes of the three into the same line. 
…with the ordinary Huyghenian eyepiece the correction is only perfect 
at the centre of the field.  It is necessary to separate the lenses of 
the eyepiece considerably (and the proper point may be determined by 
experiment) to insure correction throughout the whole field.   I had 
the field lens mounted in a  separate tube, and by sliding out the tube 
determined the best position.  The tube was then fastened.  This 
opening of the lenses interferes slightly, perhaps, with marginal 
definition, but not seriously; and when the adjustments were all 
properly made, the lunar craters and brilliant points of the 
terminator, when the moon was viewed, were free from colour throughout 
the whole field, and a planet would cross the field from one side to 
the other, showing only the fringes of the secondary spectrum,  light 
green, or wine-coloured, as the eyepiece was a little without or within 
focus.  The want of centering shows itself at once in the planet or 
other object appearing free from colour nearer one edge of the field 
than when in the middle; of course, a lateral movement of the eyepiece 
will bring the centre into the proper position….the one I constructed, 
and which was eventually mounted equatorially... has long since passed 
out of my possession. ….After numerous experiments, I concluded that 
with 6 in. aperture the penetrating power was quite equal to that of 
the telescope by Tully, used by Captain Smyth at Bedford, showing 
readily stars marked as the 'minimum visible' with that instrument.  
Considering that the lenses were ground only to the nearest radii to 
the curves I had required, which the optician (a manufacturer of 
photographic lenses) possessed, and which differed often more than 1-
10th inch from my own curves, I think it will be apparent that the 
instrument has a considerable range of correction within itself.  I 
neglected to state that after the holder of the corrector was in place, 
the tube containing the correcting lenses was brought into final 
position by pushing with a long stick introduced inside the telescope 
tube.
.…the mode of illuminating opaque objects by means of light thrown down 
through the objective itself.  I first employed that mode of 
illumination, and subsequently adopted as preferable, a perforated 
metallic speculum; the first instrument which I sent over to England, 
and which had such a reflector, was shown.…Not having read my article 
in Silliman's Journal, Messrs. Powell and Lealand, and also Mr. Beck, 
conceived that a glass disc or plate would be better than the 
perforated silver reflector which I had adopted; I believe they still 
make them thus.  The effect is not as good as that given by the 
metallic speculum.      H.L. Smith, Hobart College, Geneva, N.Y.
---------
Smith holds U.S. patent 52,901, Feb. 27, 1866, for a microscope with a 
reflector in the tube for transmitting light through the objective onto 
an opaque object.  This patent contains the unusual language, "I do not 
wish to confine myself to the precise mechanical arrangement shown in 
the drawings."  
--------

Smith, H.L. On Telescopes of Short Focal Length. The Sidereal Messenger 
1:9 (Jan. 1883) 239-243.  (synopsis)
   In No. 28 'Science Observer', Smith wrote on an excellent short 
focus Tolles.  'Dumpy' reflectors by Short, Watson, and others were 
short focus reflectors that performed well but were difficult to 
correct & thus expensive.   The first large achromat in America, a 5 
inch Dollond triplet, 10 feet focus, at Yale, objective full of bubbles 
and specks, but an excellent, unrivalled glass.  Less than f15 usually 
thought unadvisable: requires thicker discs, far more skill in 
correction.  Clarks have not worked in this area, their comet seekers 
not indended for double stars.  Steinheil and Tolles have been 
successful with short focus telescopes, and recently John Byrne as 
well.
   "In the division of close double stars, highest excellence of 
figure, and consequent corrections, are not alone sufficient; the 
magnitude of the spurious images set a limit to the separating power.  
I have not Airy's treaties on the undulatory theory by me at present to 
refer to, but I am pretty certain that he gives the extreme diameter of 
a star disc, in seconds of arc, to the first black ring, 5.52 / 
aperture."
   Smith notes that a double can be resolved using full aperture but 
not with an aperture mask in place, even though the same magnification 
is in effect.  He seems to extrapolate that a lower f ratio is the 
cause (rather deducing that an increased aperture provides greater 
resolution).  
   He describes the excellent performance of a 4 1/4 inch Byrne of 38 
inch focus, especially used with a Tolles 1/4 inch solid eyepiece.  
This telescope shows closer doubles than one of equal aperture & 
ordinary focal length, and allows use of lower magnifications - the 
objects he cites are visible at lower power with this telescope.  All 
controls are within reach & the instrument is far easier to handle than 
a standard telescope.
   "I am pretty certain that Mr.Byrne could make a telescope say 9 inch 
aperture and seven feet focal length, that would separate any double 
star now known, and prove a fair match for some of the gigantic, and 
necessarily more or less unwieldy instruments, bending under their own 
weight. …I have already named Mr. Tolles' success with a telescope of 
the same size.  That telescope is now doing good service in China, 
where it was taken by one of my pupils."
---------

E. P. Mason and the nebulae  (edited)  
Ashbrook, Joseph.  The Astronomical Scrapbook. Cambridge: C.U.P., 1984.  
Reprinted from: Sky & Telescope, Dec. 1972, p366. 
Ebenezer Porter Mason.   In 1835 the 16 year-old Mason entered Yale 
College, where as an undergraduate, he and two classmates built the 
largest telescope in the United States.  The professor of astronomy was 
Olmsted, an outstanding teacher who wrote clear and thorough textbooks 
and encouraged his students to do practical observing.  Yale in 1830 
had acquired a 5 inch Dollond refractor of good optical quality, but 
with a crude altazimuth mount on casters, so that the instrument could 
be pushed from one window of the octagonal observing tower to another.  
It was with this instrument that Olmsted and Elias Loomis (1811 - 1889) 
recovered Halley's Comet on August 31, 1835.  Borrowing a 6 inch 
Herschelian reflector from a classmate, he made observations of 
Jupiter's satellites, the rings of Saturn, occultations, and other 
phenomena.  Soon after, Mason and several friends made a number of 
small Newtonian and Herschelian telescopes with speculum metal mirrors.  
'One of Mason's letters gives an account of an evening in his room 
devoted to figuring a mirror with two classmates, each one taking his 
turn in the tedious task until a late hour, with frequent trips 
outdoors to make a hasty test sight of the stars, for the Foucault test 
was then unknown.'  At that time the largest telescope in America was 
perhaps the 8 1/2 inch reflector built by Amasa Holcomb of Southwick, 
Massachusetts, and exhibited by him in 1835 at the Franklin Institute 
in Philadelphia.  The Yale students surpassed this with a 12-inch 
Herschelian of 14 feet focal length.
   Mason gives these details: 'The instrument was first planned and 
begun in the summer of 1838, by my friend and classmate, Mr. H.L. 
Smith.  A tolerably good metal was cast, after several failures, and 
the speculum was finally polished near the close of the summer.  Mr. 
Smith and Mr. Bradley shared the expenses attending the formation of 
the mirror and erection of the telescope, and divided the long labor of 
grinding the speculum, and I united with them in the less tedious task 
of giving the mirror its final polish and figure.  The mode of mounting 
the telescope was similar to Ramage's, but ruder.  The base consisted 
of three beams, forming a triangle, which revolved on a circular ledge 
of plank, by means of rollers at the angles, and which was guided truly 
in its circuit by a crosspiece, through which rose a central bolt, 
firmly driven into the ground.  From the angles of this base rose three 
beams, meeting at a height of sixteen or seventeen feet from the 
ground, and a rope passed through a pulley fixed at this height, and 
sustained the weight of the upper part of the telescope.  The lower 
end, containing the speculum, rested on a small platform at one of the 
solid angles of the base, and revolved with the frame.  The quick 
motion in altitude was by means of the rope just mentioned, which 
passed down to a windlass at the base, while a slow motion was gained 
by a ... combination of ropes within the immediate command of the 
observer.  In azimuth, the whole frame could be wheeled about by a 
single person, and a slower motion was obtained by simply swinging the 
telescope by hand, which could be done by the observer, in following a 
star, with perfect steadiness.'
   Smith was chiefly responsible for building this big telescope, but 
Mason led the way in putting it to scientific use.  In the summer of 
1839, he and Smith made a detailed study of the Trifid and Omega 
nebulae in Sagittarius, and the Veil nebula in Cygnus.  Their purpose 
was to obtain accurate descriptions and delineations for use in 
detecting possible future changes; published in a 49 page paper in the 
'Transactions of the American Philosophical Society'.  For each nebula, 
Mason began by carefully charting all the faint stars in its vicinity 
to furnish reference points.  Many of these stars were measured with 
the 5 inch refractor and filar micrometer.  This operation was 
difficult with an altazimuth mounted instrument since the micrometer 
had to be reoriented for each measure.  Other stars were plotted by eye 
estimation.
   In addition to making meticulous pencil drawings of nebulae, Mason 
was probably the first astronomer to prepare brightness contour maps.  
A contour map of the Trifid nebula was made, in which the 'isophotes' 
depend on visual estimates rather than photometric measurement.  He 
defined the innermost contour line as that one 'imagined to surround 
all those portions of the nebula which are of uniform brightness, and 
brighter than any other part.'  The next outer line represents 'the 
first perceptible gradation or diminution of light,' and so on, until 
the outermost contour, 'which represents the utmost bounds of the 
visible nebula.'  In practice, Mason visualized each line as winding 
its way among the stars of the field and then drew it on a star chart.
   Smith graduated from Yale in 1839, took 12 inch telescope to Ohio 
City, Ohio, and remounted it, but its further fate is unknown.  Smith 
taught at Hobart College.
---------------
Olmsted, Dennison, The Life and the Writings of Ebenezer Porter Mason.
The article of Mason on the Nebula, published in the American 
Philosophical Transactions for 1840, was his most elaborate work, 
occupying about fifty pages quarto...It contains a description of the 
large telescope constructed by the joint skill and labor of himself and 
his classmate Mr. H. L. Smith, his own observations on four remarkable 
nebulum, two of them in part or altogether his own discover-  We copy 
one passage from his description of the telescope, in which he notices 
the effect of the atmosphere upon its magnifying power. if we mistake 
not, it will be admired by the rhetorician for its elegance, as well as 
by the astronomer for its singular precision in the statement of a 
troublesome difficulty.
    But the chief bar to magnifying power is in the atmosphere. The air 
is seldom so well balanced as to be without contrary currents and 
motions, which produce slight transitory undulations and variations of 
density. In a section of the broad beam of light which is to enter the 
telescope, there is room for considerable momentary differences of 
density, and consequently of refraction. When the rays before incidence 
are thus irregularly deflected from perfect parallelism with each 
other, and quivering or vibrating about a mean state, the point of 
light which they form after reflection must be troubled and confused. 
The star in the field of view is in constant and rapid agitation, like 
an object seen through smoke or heated air, or the image of the sun on 
gently rippling water. According to different circumstances of 
atmospheric disturbance, the appearances of the star to an attentive 
observer are very different. Sometimes the individuals of a close 
double star twirl round each other, altering much their angle of 
position; sometimes it appears like a drop of agitated mercury,… 
breaking in pieces and reuniting, occasionally heaving gently like the 
sun reflected on a calm swell ; and the rarest of all states is that of 
perfect rest. These motions are minute, but are excessively 
troublesome, and in the majority of evenings prevent the application of 
very high powers, or the separation of very close and difficult stars. 
An excellent telescope might very easily be condemned for supposed want 
of optical capacity on an unfavorable evening. Its merits therefore 
should not be judged of too hastily, nor until several evenings patient 
trial. And unless the star is free from any rapid quivering or 
agitation, it cannot be judged whether the atmosphere or the telescope 
is most in fault.  --Ebenezer Porter Mason. [New Englander and Yale 
review. / Volume 3, Issue 11, July 1845]
=============

Chronological Bibliography:

American Journal of Science (First Series) 35 (1839) 174-5.

Observations on Nebulae with a Fourteen Feet Reflector, made by H.L. 
Smith and E.P. Mason, during the year 1839. Transactions of the 
American Philosophical Society 7 (1841) 165.

Smith, Hamilton L. Reflecting Telescopes. Annals of Science 1 (1853) 
104-105, 117-118, 127-128, 141-142, 188-189, 200-201.

Smith, Hamilton. Memoir of Charles A. Spencer.  Proceedings of the 
Society of Microscopists (1882) 49-74.  Reprinted in: Three American 
Microscope Builders. Buffalo: American Optical Co., 1945.

Smith, H.L. On Telescopes of Short Focal Length. The Sidereal Messenger 
1:9 (Jan. 1883) 239-243.

Ashbrook, Joseph.  E. P. Mason and the nebulae.  The Astronomical 
Scrapbook. Cambridge: C.U.P., 1984.  Reprinted from: Sky & Telescope, 
Dec. 1972, p366.  
Citations include:  T.R. Treadwell, 'Notes on a Forgotten Episode', 
Popular Astronomy 51 (1943) 497.

===================

home page: http://home.europa.com/~telscope/binotele.htm