made upon mediums for protecting the eyes from the
direct light of the sun, and also upon the best form and material for a
back-ground to the likenesses. The length of time required for a
"sitting," even with the reflecting apparatus, was such as to render
the operation anything but pleasant. Expedients were ever ready in the
hands of Wolcott: blue glass was tried and abandoned in consequence of
being, at that time, unable to procure a piece of uniform density and
surface: afterwards a series of thin muslin screens secured to wire
frames were prepared as a substitute for blue glass. The objections to
these screens, however, were serious, inasmuch as a multiplication of
them became necessary to lessen the intensity of the light sufficiently
for due protection to the eyes, without which, the likenesses, other
than profiles, were very unpleasant to look upon. Most of the
portraits, then of necessity were profiles formed upon back-grounds,
the lighter parts relieved upon black, and the darker parts upon light
ground; the back-ground proper being of light colored material with
black velvet so disposed upon the light ground, this being placed
sufficiently far from the sitter, to produce harmony of effect when
viewed in the field of the camera. Other difficulties presented
themselves seriously to the working of the discovery of Daguerre, to
portrait taking--one of which was the necessity for a constant and
nearly horizontal light, that the shaded portions of the portrait
should not be too hard, and yet, at the same time, be sufficiently well
developed without the "high light" of the picture becoming overdone,
solarized or destroyed. In almost all the early specimens of the
Daguerreotype, extremes of light and shade presented themselves, much
to the annoyance of the early operators, and seriously objectionable
were such portraits. To overcome this difficulty, Mr. Wolcott mounted,
with suitable joints, upon the top of his camera, a large looking-glass
or plane reflector, in such a manner that the light of the sun (as a
strong light was absolutely necessary), when falling upon the glass
could be directed upon the person in an almost horizontal direction.

Early in February, 1840, Mr. Johnson, Sen., (since deceased) sailed for
Europe with a few specimen likenesses taken with the instruments
completed as above, with the intention of patenting the invention. On
his arrival a joint arrangement was effected with Mr. Richard B