8b
QH
211
. C37
1891

THE

Franklin institute

LIBRARY

The

Elihu Thomson
Collection

Given by Mrs. Elihu Thomson

CLASS BOOK

ACCESSION

\

REFERENCE

No. 29.

Carl Zeiss

OPTISCHE WERKSTATTE

Jena.

microscopes

AND

MICROSCOPICAL ACCESSORIES.

1891.

The following Catalogues may also be hart gratis on application

Illustrated Catalogue of Photographic Objectives.
Catalogue of Optical Measuring Instruments.

Library

r * THE r > *

franklin

INSTITUTE

THE GETTY CENTER
LIBRARY

Terms.

Each article specified in this Catalogue may be supplied singly or in
sets at the prices subjoined.

The price of completely fitted Microscopes is in all cases the sum-total of
the individual items.

The quotations are understood: goods delivered at Jena, packing charged
extra, net cash without any reduction, cheques upon a principal town in
Germany, England or France being also accepted.

Goods are forwarded, value insured, at the risk and cost of the buyer.
In case of special shipping instructions not being given foreign orders will be
despatched by the best possible route and with every precaution.

It is requested that name and address be plainly written
in all orders and, to prevent mistakes, that the number or date
of this Catalogue be quoted.

Jena, 1891.

Carl Zeiss,

Optische Werkstatte.
Telegrams: “Zeiss Werkstatte Jena”.

A selection of completely fitted Microscopes for the most varied
requirements will be found at the end of this list.

We shall be glad to supply for scientific publications electros of the
figures contained in this catalogue. Some of these also in reduced sizes.

Unauthorized reproductions of the figures or text of this catalogue
are prohibited.

Contents.

page

Objectives and Eye-pieces . 1

Apochromatic Objectives . 7

Compensating Eye-pieces . 15

Projection Eye-pieces . 18

Achromatic Objectives . 19

Huyghenian Eye-pieces . 23

Accessory Apparatus for testing Objectives . 24

Stands . 26

Specification and Prices of the various Stands . . 32

Accessory Apparatus for the Microscope

Illuminating Apparatus . 57

Appliances for changing the Objectives on the Stand . 67

Apparatus for measuring and counting microscopical Objects 70

Drawing Apparatus . 77

Arrangements for Polarisation ... 79

Spectroscopic Eye-pieces . 81

Various optical and mechanical Apparatus . 85

Apparatus for Photo-micrography . 92

Dissecting Microscopes and Magnifiers . 100

Microtomes . 1 10

Slips and Covers . 112

An asterisk denotes that the apparatus or optical combination so marked
originated in our factories, i. e. was either introduced by us as new or , at any
rate, first made by us in the manner here described.

Objectives and Eye-pieces

In our previous catalogue (No. 28, issued in 1889) we referred to the
advance made, through our efforts, a few years previous to the publication of
that catalogue, in the practical development of the microscope. It was there
pointed out that this advance was, in a great measure, due to the results obtained
in the production of new glasses (borate and phosphate glasses in particular)
by the “Glastechnisches Laboratorium Schott and Genossen”, which has been
established here, with our cooperation, as the outcome of long continued ex¬
periments by Dr. Schott and Prof. Abbe. By the use of these new glasses,
which by their properties with respect to refractive power and dispersion con¬
stitute a much superior material for the construction of microscope lenses, and
the application of new formulae in the construction of the lenses, we have, since
1 886, produced microscope objectives which possess a considerably m ore
perfect correction both of chromatic and spherical aberration,
and therefore a much greater concentration of light in the image, than had hitherto
been attained. We also introduced eye-pieces specially adapted for use with these
objectives, which, in addition to other advantages of minor importance, produce
almost perfect achromatism and give a sharp image over the whole visual held.

These new combinations which were first published in August 1886 under
the designations “Apochromatic Objectives” and “Compensating Eye-pieces” and
"Projection Eye -pieces” are now extensively used and appreciated (we refer to
the numerous comments in various scientific and technical periodicals and works),
and have stood the test to which they were put as a means of advanced scientific
research. At the request of eminent microscopists the series of these objectives
has been increased by the addition of a few n e w types (vid. below).

(Batl & pti|Ac fyVizkftaUt, ckna.

The present catalogue includes, in addition to this new series, most of our
older achromatic objectives and ordinary eye-pieces. For although there is every
reason to assume that in the course of time the apochromatic lenses, at least in
the more difficult departments of microscopical research, will entirely supplant
the older objectives, yet there are a great many problems in microscopy that do
not demand the highest attainable degree of perfection for their solution and in
the plurality of such cases the former achromatic microscope will be all that is
needful, provided it is good of its kind and judiciously and carefully made.
The objectives and eye-pieces of the older type have certainly this advantage that,
thanks to their much simpler construction, really good lenses of this class can
be supplied at considerably lower prices than the lenses of the new series which
are much more complicated and involve in their production an extraordinary
degree of manual skill.

For these considerations we have, in publishing the last edition of our cata¬
logue, omitted from the list of our former objectives only those numbers whose
special purpose is at present undoubtedly better realised by the apochromatics
— namely a few of the low power dry lenses of relatively large aperture and
the very short and very long focus lenses in the series of water and homogeneous
immersions.

The original achromatic objectives, moreover, have been
considerably improved in detail by the use of the new varieties
of glass and such other alterations as their type of construction
permitted. The higher powers of these lenses — both of the dry and immersion
series — where the advance thus effected is relatively considerable, might be
termed, after the example of other makers, “s emi- a p o c h r o m a t i c 1 e n s e s”.

The original prices of these systems have not sustained any change by
these improvements.

In the special catalogue of 1886 we made a beginning and introduced
a rational system of designation of the objectives and eye -pieces of
the new series in contradistinction to the prevailing purposeless and arbitrary
method.

Although we consider this system to be more practical than any of the
usual conventions of lettering and numbering, and though its universal adoption
would constitute a decided step in advance, we consider it nevertheless wiser
to desist, for the present, from redesignating our older (achromatic) objectives.

o

O

Great alterations in tlie focal lengths of both objectives and eye-pieces would
have been necessary in order to designate these by the same convenient round
numbers as in the new series. Our microscopes, however, being in such extensive
use, so many microscopists have become accustomed to the focal lengths hitherto
adopted and the usual denotation of the various combinations, that a radical alteration
in this direction might give rise to considerable confusion. For these reasons the
former designation of the objectives by letters and the arbitrary numeration of the
eye-pieces has been retained in the older series.

I

The manufacture of all our objectives is based upon a method of complete
theoretical computation of all the constructive types previous to their actual manu¬
facture. By this process, which was introduced by Prof. Abbe in our works
in 1868 and has since been adhered to by us, it has become possible to employ,
through judicious division of labour constantly controlled by scientists, a large
number of persons in the production of articles of the greatest possible perfection.

Strictly mathematical computation of every detail of construction combined

with exact technical methods of working and a systematic control of each phase

of manufacture, obviate all empirical tests and ensure extraordinary uniformity

of our lenses from the highest to the lowest powers, at the same time altogether

excluding specimens of inferior quality. All objectives are uniformly free from

spherical aberration up to the marginal zone (proper thickness of cover with

the higher powers being understood) and, as far as possible, perfectly corrected

for colour. Special consideration is also given to the removal of aberrations in
«

the extra-axial part of the held and to hatness of held.

Working Distance. Owing to the importance of a good working distance
for the convenient and safe employment of the higher powers, particular attention
has been given to this factor in calculating the formulae of the various glasses.
Our higher objectives possess therefore unusually large working
distances, in comparison with their focal length and aperture.

Tube Length. All the objectives named in this catalogue are adjusted
for a tube length of 160 mm ( ( > 1 / 2 in.), except where a remark to the contrary is
expressly made in the following pages or unless an objective for another tube
length be specially ordered. The length is reckoned from the contact surface of
the objective thread to the upper end of the body on which the eye-piece rests.
This may be read off directly on stands of our make by the divisions on the
draw tube.

The objectives a, aa. A, 13 a n d C may be used on t h e 1 a r g e
English stands with 10- inch tubes without appreciable loss.

o

All the others, particularly the apo chromatic series and
also the homogeneous immersions, perform more or less defi¬
ciently on stands o f E n g 1 i s h model, unless specially adjusted
for these.

In foreign orders it should always be stated whether the
objectives are to be adjusted for the short (continental) or for
the long ( English ) tube.

Thickness of Cover. All objectives in fixed mounts are, unless otherwise
ordered, corrected for a medium thickness of cover between 0.15 and 0.20 mm.
In the higher series (from the apochromatic 8 -mm and achro¬
matic D upwards) the thickness of cover corresponding to the
most perfect correction is indicated on the side of the mount by
small figures (millimeter). It is, as a rule, sufficient for ordinary work
with those objectives which we supply only in fixed mounts, to use covers of
an estimated medium thickness.

Homogeneous immersion ob¬
jectives are, within wide limits, inde¬
pendent of the thickness of cover.

Correction Adjustment. The gra¬
duation and numbering on the correction
collar, read off on the fixed index, indicates
directly for each position of the collar
the corresponding thickness of cover (in
hundredths of a millimeter) which yields
the best correction for that position. The
correction for cover must be carefully ad¬
justed, particularly in the case of the apo-
chromatics 4.0. 3.0 mm (dry) and 2.5 mm
(water immersion) and the achromatic
lenses F and J, failing which the ef¬
ficiency of the lenses will be greatly
diminished.

The homogeneous immersion ob¬
jectives are only supplied in fixed
mounts beause, as already stated, their
efficiency is within rather wide limits

Fig. 1.

The correction ring b serves to adjust the
distance between the upper part tl of the system
Hiid the lower part e which is attached to the
mounting a.

(2cuf iScioa, 0pttjkhc -ftattc, Skua.

6

independent of thickness of cover-glasses and also because any alteration in the
distance of their lenses interferes with the perfection of their correction. Con¬
siderable variations in thickness of cover are best compensated for
by slightly lengthening the body-tube for thinner covers,

,, „ shortening „ „ „ thicker ones.

On page 211 it is shown in what manner the thickness of cover -glasses of
a mounted specimen can be easily ascertained by means of our stands.

Tlic immersion fluid which we recommend for the homogeneous objectives
is Cedar- wood oil (from Juniperus virginiana) which we have used from the
first. We supply the same in a thickened condition, which not only does away
with its inconvenient fluidity, but at the same time yields almost perfect identity
of refractive index with that of the cover -glass. A bottle of this oil is supplied
with each objective and may be procured from us at any future occasion (price
M. 0.75 pr 1/2 oz bot). We expressly request, that no immersion
fluids derived from other sources be used with our objectives,
or at least none which have not been carefully tested as to their
proper refractive power — as is done by us — because the use

of unsuitable fluids implies considerable loss in the optical

*

p e r f o r mance o f the object! v e.

As regards the relative merit of the homogeneous and non¬
homo g e n e o u s (water etc.) immersion systems, the former claim superiority
over the latter (focal length and aperture being equal) by reason of their eminently
superior defining power and their greater insensibility as to variations of thickness
of cover - glasses. Water immersion systems are only to be preferred in such cases
where the nature of the objects does not admit of oil being used as immersion fluid.

The mounts of all objectives are provided with the English standard
thread of about 20 mm external diameter. In the series from A to J however,
and also in DD when not fitted with correction adjustment, the lower part of the
mount containing the lenses is made to unscrew from the adapter and may then
be used with the narrow-gauge thread.

The name of our firm is engraved on the mountings of all objectives, on
the apochromatics also the aperture, focal length and tube length for which they
are adjusted and on the ordinary glasses the letter by which they are designated.

When ordering objectives which are intended for use with
stands not made by us, it is in all eases, where these are not noted
for haviny the same screw-thread and internal diameter of tube,
advisable to send the tube in question for the purpose of adaptiny
the objectives and eye -pieces.

* Apoehromatie Objectives.

While referring to the paper of Prof. Abbe, entitled “Ueber Verbesserungen
des Mikroskops mit Hilfe neuer Arten optischen Glases” (Sitzungsberichte der
Med.-naturw. Gesellschaft zu Jena vom 9. Juli 1886) J) and to the forthcoming
work of our colleague Dr. Czapski on the “Theorie der optischen Instrumente"
(Breslau 1893, Trewendt), which combine to furnish a complete exposition of the
scientific aims and principles which governed the construction of the apoehromatie
lenses, we must here content ourselves in briefly stating the essential features
of these lenses.

These objectives essentially differ from all other microscopical lenses hitherto
constructed by the simultaneous realisation of the two following conditions : viz.
1) the union of three different colours of the spectrum in one point of the axis,
that is to say, the removal of the so-called secondary spectrum inherent to
the older achromatic lenses, and 2) the correction of spherical aberration for two
different colours in contradistinction to that for one in the brightest part of the
spectrum only.

With all optical systems hitherto constructed , microscopes included , the
sharpness of the image projected is limited to one particular colour of the light
transmitted (i. e. green -yellow in the case of lenses used for ocular observations,
blue-violet in photographic lenses), while the other rays give more or less confused
images, appearing partly as colour fringes and partly as a general blur. With the
apoehromatie lenses, however, the projected images are nearly equally sharp for all

1) Sent gratis on application.

Qait % iiss, 0pti fche fyVettiftdUe, 3tna.

8

colours of the spectrum, and the quality of the projected image is, therefore, within
wide limits independent of the nature of the illuminating source, which may be
white or compound, or monochromatic light emerging from any section of the
spectrum.

In the older series again complete colour correction is obtained for
one zone of the objective only, a marked deterioration being observable towards
the margin and the centre of the aperture, whilst in the apochromatic lenses it is
corrected uniformly for all zones. Consequently, in using Abbe’s test-plate, scarcely
more colour is perceived with the most oblique illumination than with central light.

Finally, even within the zone of the most complete colour correction of the
ordinary achromatics, only two colours can be united in one point. The various
coloured images therefore can only fall on the same spot in pairs between which
there is a considerable difference in focus. In the new series, however, three
colours are brought to a focus, whereby the amount of focal difference for the
various sections of the spectrum, from the visible to far into the chemically active
portion, is reduced to ’/7 to 1/l0 of its original magnitude i. e. practically
eliminated, and this, as has been stated before, equally for each zone of the
objective. The images due to each single colour, thus individually corrected, are
rendered coincident und collectively form the final image 1).

The practical advantages of these new lenses become at once apparent.
A considerably increased concentration of light with ordinary eye -piece observ¬
ation or any other mode of application under all possible conditions of illumination
confers on these glasses an acknowledged superiority over the ordinary achromatic
lenses both with respect to optical capacity and diversity of applicability.

The natural colours of objects, even in the more delicate tints, are

*

truly reproduced by these objectives. Close to the margin of the field,
the images are nearly as sharp as in the centre, though the high aperture
and the relatively great working distance render a moderate degree of curvature
of the image unavoidable in these objectives as in the older ones; the central

1) It would be a grave error, both theoretically and practically, to viewr this
process of achromatisation of a higher order as here defined in the light of
a mere improve m ent of ordinary “achromatism” , such as would result from
a diminution of the secondary spectrum while yet only two colours are united, or
from achromatisation embodying the principles here indicated but limited to one
particular zone of the objective (which might be obtained by the introduction of
suitable glasses into objectives constructed after the usual formula).

The word “apochromatic” was introduced by Prof. Abbe as a technical term
for this other kind of achromatism, long familiar to scientists as a theoretical
idea but only recently realised practically. With deference to intelligible technical
phraseology it is desirable that this expression thus clearly defined by its author
should retain its original meaning, and any attempt to utilise it for
purposes of trade advertisements should be discountenanced.

9

and marginal portions of the field do, therefore, not appear in sharp focus
simultaneously, but have to be focussed in succession.

As a result of the great concentration of light afforded by these objectives,
they permit of the use of very high power eye-pieces without detriment
to accuracy or brightness of the image, thus giving high magnifying power with
relatively long focal length, thus yielding with the same objective a series of
very varying amplifications.

In the annexed list beside the apertures and foci the corresponding
objective magnification is stated, i. e. the magnification which the ob¬
jective alone would give at the distance of distinct vision if used as a simple
lens. This is simply 250 (distance for distinct vision) divided by
the focal length of the objective in mm. For instance, the
objective magnification of a 3-niin objective is:

^ = 83.3.

o

The apertures indicated are the guaranteed minimum values; the

stated focal lengths are adhered to as closely as possible.

Remarks on the use of the 2-mm Apochroinatic Lens of 1.40 mm aperture

(homogeneous immersion).

Owing both to the hyper-hemispherical form of the front lens, which is held
in situ by a very narrow ridge at the extreme edge of the setting, and its rela¬
tively short working distance (0.2 mm) this lens demands careful treatment
and should, in particular, be scrupulously guarded against shocks or pressure.
As compared with the 2-mm lens of 1.30 aperture this lens possesses a greater
resolving and defining power in the proportion of 14 : 13 and gives a brighter
image in the proportion of 20 : 17. The 2-mm 1.40 is a decided advantage where
exceptionally intricate problems requiring the most delicate apparatus
have to be solved, and also in such cases where the lens is to serve as a means
of controlling observations made with lower powers ; for r e g u 1 a r w o r k
preference should be given, generally speaking, to the 2-nnn 1.30, owing, to the
greater firmness of the frontal lens.

The objective 3-mm 1.40 apert. has, however, this advantage over the 2-mm
1.40 that, while possessing the same optical capacity, it has a greater working-
distance and is also less delicate as regards its mechanical construction.

Qaz-t Siiw, (£)pti|4ve dtna.

Iii reply to numerous enquiries and, in some cases, publicly expressed
doubts respecting the

durability of apocliromatic lenses

we append the following statements.

All glasses used in the construction of apocliromatic lenses have been
amply tested through several years’ experience and olfer a fair guarantee for their
immutability, at any rate in temperate climates and on condition that the lenses
are not subjected to any undue treatment. This statement does, however, not
apply for the present to suit hot climates where an exceptionally damp and hot
atmosphere constitutes an abnormally active decomposing agent, which even the
older (silicate) glasses do not permanently resist; in these cases we disadvise
the use of apocliromatic lenses. A few isolated cases have indeed occurred even
in our climate in which the one or the other of the constituent lenses of certain
apocliromatic systems have become turbid; but it would not be fair to hold us
responsible for such contingencies. For be it remembered, the introduction of
apocliromatic lenses by us necessitated the application of entirely new materials
which until then had not been used or tested. The first lenses, necessarily,
lacked the kindly aid of experience and it is not surprising that a few failures
should have occurred. Whereever varieties of glass used in the construction of
lenses proved to be liable to deterioration, the lenses containing such glasses
were subjected to reconstruction and all doubtful glasses supplanted by such
that were known by experience to possess greater durability. Even as now
constructed the apocliromatic lenses are sensitive with respect to moist stagnating
air and in damp hot climates ; it is, therefore, advisable to keep the lenses, when
not in use, in air-tight receptacles.

As in former cases we shall also in future in any such cases, where one
of the lenses of an objective supplied by us should exhibit spontaneous changes,
not hesitate to repair the damage at our cost. To this promise we attach however
the condition that the objective in question be sent to us previous to any
attempt being made in this direction by others. In no case should
such an objective be disconnected, with a view to clean it, by any other but an
expert, as this might suffice to convert a slight irregularity, that could be easily
corrected by us, into a serious or even irreparable defect.

11

New Lenses.

At the request of eminent microscopists we have added to the series of our
apochromatric lenses the following types:

1) two objectives of v e r y low p o w e r for the purposes of p h o t o - m i c r o -
graphy (serial sections etc.) and for projection on a screen — viz. 70-mm
and 35-mm projection systems;

2) two obj ectives of large aper t u r e and a shorter focus (for an
increased initial amplification) as compared with the older types — viz.

3-mm apocliromatic dry system of 0.95 apert. and 1.5-mm apocliromatic
homogeneous immersion lens of 1.30 apert.;

3) an obj ective having the greatest aperture attainable with the
present optical means — viz. 2.5-niin monobromide of naphthaline immersion
objective of 1.60 apert.

ad 1. The systems of 70 and 35 mm focus serve, as stated above, for
p h o t o - m i c r o g r a p h y and projection exclusively. Of these the former can
only be used in conj unction with the photo - micrographic stand, the latter,
however, may be used with any of the other stands.

The 35-mm lens screws to the lower end of the tube in the usual manner.

The 70-mm lens requires a special conical adapter, which is supplied with
each lens, to insert it into the upper end of the tube.

Both are used without eye-pieces.

As a condenser it is best to use a convex lens of a suitable focus (price of
lens mounted in sleeve M. 5. — ) to concentrate the rays of the source of light
upon the objective, so that the pencil of rays emerging from this lens may
traverse the object before coming to a focus.

Gait Seiii, 0ptij’ave tyVithftatU, cbna.

12

In order to predetermine by calculation the amplifications obtainable from
these lenses, the distance of the image (i. e. of the focussing plate) from the ob¬
jective has to be divided by its focal length, i. e. by 70 and 35 respectively and
the quotient so obtained is to be diminished by unity, in accordance with the
well known formula.

Prices :

Projection lens of 35 mm focus M. 35. —

V 1) M 70 )) M M 4:0*

ad 2. The two newly constructed apochromatic objectives of relatively short
focus present the same principal features as all the older types of this class of
lenses. In particular, they require the use of “Compensating oculars”, with this
exception, however, that — in consequence of the relatively greater initial ampli¬
fication of the new systems — the highest numbers of eye-pieces should not be
used with them, it being in the case of histological and bacteriological investigations
not even advisable to go beyond the No. 8 eye-piece.

ad 3. In autumn 1889 we constructed a system which sensibly exceeds
with regard to defining power the limits which had existed for the then known
objectives whose apertures were of necessity numerically less than the refractive
indices of crown-glasses. The objective has an aperture of 1.60 to 1.63 with a
focus of 2.5 mm and may satisfactorily be used with the ordinary compensating
eye-pieces. The slight traces of colour which are observable near the margin of
the field may, if thought necessary, be neutralised by adapting a correcting lens
to the eye-pieces No. 8, 12 and 18. Pure monobroinide of naphthaline serves as
the immersion-fluid to this objective, and a small bottle of it is supplied with
each objective. The specimens have to be covered with carefully polished flint
cover-glasses having an exactly calibrated thickness (of ab. 0.17 mm) and must
be embedded in media of a refractivity exceeding 1.60 (e. g. monobromide of
naphthaline, realgar, iodide of mercury, methylene-iodide, Smith’s medium etc.).

When oblique illumination or an illuminating cone having an aperture of
more than 1.40 is to be employed, flint slips, a flint-glass condenser and some
highly refracting substance connecting both — say monobroinide of naphthaline —
have to be used.

To obviate misconceptions regarding the capabilities of this lens we will not
omit to distinctly state that we do not proffer this lens as an improved means of
microscopical research directly applicable to the adopted micro-technical methods:

it has. on the contrary, been constructed for the purpose of placing in the hands of
those specially interested in the development of microscopical technique from an
optical point of view, a means of determining to what extent lenses possessing an
aperture exceeding the highest aperture obtainable under the usual conditions of
application may successfully be used in certain departments of microscopical research.
Every advance in this direction necessarily involves an increase of the external dif¬
ficulties attending the application of the lens; we are, in particular, referring to the
preparation of objects ; the difficulties to be surmounted here will be readily appre¬
ciated if it be remembered that the aperture can never be made to exceed the
refractive index of the embedding medium and the cover-glass.

Originally only a few specimens of this new objective were made as a purely
scientific experiment. The results, however, which have been obtained with it by
several microscopists , despite of the difficulties attending its application , have
encouraged us in including it in our list of objectives, and we shall continue to
make this lens as long as nothing better exists in this direction.

A detailed account of the principles of construction of this lens, its mode of
application and its capabilities will be found in the Zeitsclir. fur wiss. Mikroskopie,
VI, 1889, p. 417 — 422 (also English translation in pamphlet form), Journ. of the
Roy. Microsc. Soc. 1890, p. 11, and H. van Heurck, La nouvelle combinaison
optique de Mr. Zeiss et la structure de la valve des diatomees, Anvers 1890.

We shall be glad to forward these publications to applicants.

Qaz-i iSciao, 0pti(cA.e SlCVil Ij’talte, ckna.

List of the Apochromatic Objectives.

Numerical

Equivalent

Initial

Price

aperture

focus in mm

magnification

Marks

0.30

24.0*

10.5

140.—

16.0

15.5

100.—

0.65

12.0*

21

170 —

Dry Series

8.0

31

130 —

6.0*

42

220.— ] i |

I c o

0.95

4.0

63

180.— L a

I w O

3.0

83

200.— * i

Water Immersion

1.25

2.5

100

300.—

with cor¬
rection collar

'

3.0

83

400.—

1.30

2.0

125

400.—

Homogeneous

Immersion

1.5

167

450 —

1.40

3.0

2.0

83

125

500.—

500.—

Monobromide of

N aphthaline Immersion

1.60

2.5

100

800.—

The last named system is supplied together with Jo dint cover-glasses and
3 slips of heavy dint.

Each additional cover-glass . M. 1. —

Each additional slip . „ 2. —

Noil-achromatic Condenser of 1.60 aperture having a dint-glass front-lens
to be used with the monobromide of naphthaline immersion lens (for very oblique
or wide illuminating pencils) . M. 35. —

Monobromide of Naphthaline, per bottle containing 5 gr . . „ 1.50

* The three objectives 24-nun, 12-mm and 6-mm of the dry
series are constructed exclusively for the 10- inch tube , all the
others are adjusted either for continental or English tube.

15

Compensating Eye-pieees.

All objectives of considerable aperture, from their peculiar construction
(hemispherical fronts) exhibit certain colour defects in the extra- axial portion of
the visual field (chromatic difference of the magnification), even if perfectly achro¬
matic in the centre. The differently coloured images which combine to
form the final image (Dippel, 2nd ed. p. 225) are of different dimensions, the
blue image being greater than the red one. Whether an image be directly
projected by such an objective or whether it be examined with an eye-piece (even
of the achromatic or so-called aplanatic type), colour fringes will be observed,
increasing towards the margin of the field.

This peculiarity is also possessed by -the apochromatic objectives, and to
the lower power ones it has been intentionally imparted to a similar degree,
a means being thereby obtained to nearly entirely eliminate this error
by help of suitable eye- pieces. These are made to possess an equivalent
error of opposite sign, that is, the image formed by the red rays is greater
than that corresponding to the blue rays. Such eye -pieces therefore serve to
compensate the unequal magnification of different colours and the images appear
free from colour up to the margin of the field.

This compensatory action of the eye-pieces is manifested, particularly in the
higher numbers where the limiting diaphragm is placed outside the lenses, by the
fact that the edge of this diaphragm shows a red border, whilst the
image of the object formed at this very edge of the diaphragm is
perfectly colourless.

The setting- of the eye -pieces is so arranged that the lower focal point
of all numbers in each series lies in the same plane when inserted in the body-
tube. No alteration of focus is therefore required on changing the eye -piece,
and the “optical tube- length” (i. e. the distance between the upper focal point
of the objective and the lower one of the eye-piece), which is the standard factor
for the magnifying power, remains constant. This optical tube -length in the
continental microscopes (excluding small differences between the various objectives)
is 180 mm, provided that the length of the body, from the screw -collar of the
objective to the upper end of the tube on which the eye-pieces rest, is 160 mm.

The eye- pieces of extremely low power designated as Searchers serve the
purpose of reducing to its lowest limits the available magnification with each
objective, thereby facilitating the preliminary examination and the
labour of searching for particular points with high powers. Thus No. 1
of this series enables an objective to be employed with its own

(Pcuf ©ptifc-fw fyVitkftat te, 3i hci.

16

initial magnifying power, i. e. as if it were used as a simple
lens without an eye-piece. They will be found of special service with
immersion objectives, where great inconvenience is caused by having to change
a lens already adjusted for another of lower power.

The working eye -pieces for regular observation beginning with a magni¬
fication of 4 are likewise of entirely new construction and may be used with
advantage even in the highest numbers. The eye-point in all lies so high
above the eye-lens and the diameter of the lens itself is so large, that the usual
inconveniences attending the use of eye-pieces of short focus are entirely obviated.

Owing to the uniform position of the eye-points of the compensating eye¬
pieces any one of these may, without difficulty, be used with the usual drawing
prisms, including, in particular, the Abbe Camera. The most appropriate for the
purpose are naturally the lower powers 4 and 6.

The numeration of these eye-pieces is carried out on the principle sug¬
gested by Prof. Abbe. The number which denotes how many times an eye¬
piece, when used with a given tube-length, increases the initial magnifying power
of the objective, affords the proper measure of the eye- piece magnification
and, at the same time, furnishes the figures for rational numeration. On this
basis the series of our compensating eye -pieces is arranged according to their
magnifying powers, which are respectively 1, 2, 4. 6, 8, 12, 18, (27), and these
figures likewise serve as their designation.

The magnification obtained by combining a compensating eye-piece with any
apochromatic objective is arrived at directly b}^ multiplying its number by the
initial magnification of the objective as given in the preceding table. An
objective of .3.0 mm focus for example yields in itself a magnification of 83.3 (cal¬
culated for a conventional distance of vision of 250 mm); eye-piece 12 therefore
gives with this objective 12X83.3 = 1000.

For the continental and the English model microscopes
two distinct series of compensating eye -pieces are made. The
corresponding numbers in both series are of a different focal length according
to the different lengths of the tubes.

The eye- pieces 1 and 6 are only made for the continental ,
27 only for the English tube.

An order for eye- pieces to be used on stands which are not
of our make should be accompanied by an exact impression of
the edge of the tube in sealing-wax or some other exact gauge of
the internal diameter of the tube; the best gauge , will , in all
cases , be the tube itself.

17

List of Compensating Eye-pieces.

Searcher

Eye-pieces

W orking Eye-pieces

Eye-piece No. :

1

2

4

6

8

12

18

27

Equivalent focal
length in mm

180

90

For t

45

le conti

30

nental t

22.5

ube :

15

10

—

Price: Marks

20

20

20

20

30

30

25

—

Equivalent focal
length in mm

—

135

For

67

the Enj

glish tul

34

le :

22.5

15

10

Price: Marks

—

25

25

—

35

30

30

25

Table of Magnifications of the Apochromatic Objectives
with the Compensating Eye-pieces

for an image distance of 250 mm.

Focus of
the

objective

Searcher

Eye-pieces

Working Eye-pieces

1

2

4

6

8

12

18

27

24.0

—

21

42

—

83

125

187

281

16.0

15.5

31

62

94

125

187

281

—

12.0

—

42

83

—

167

250

375

562

8.0

31

62

125

187

250

375

562

—

6.0

—

83

167

—

333

500

750

1125

4.0

62

125

250

372

500

750

1125

—

3.0

83

167

333

498

667

1000

1500

—

2.5

100

200

400

600

800

1200

1800

—

2.0

125

250

500

750

1000

1500

2250

—

1.5

167

333

667

1000

1334

2000

3000

—

(2cuf ScZvis, 0ptv^cfu pat tv, ckna.

18

*Projeetion Eye-pieees.

These are used for projecting the image formed by the objective on a screen
for demonstrating purposes or upon a photographic plate. They consist of a
convex lens and a compound system , which is most carefully corrected both
spherically and chromatically after the principle of apochromatic lenses, and is
entirely free from secondary chromatic aberration and from difference of
focus between the visual and chemical rays. A diaphragm is placed
between the lenses for limiting the field, and the compound lens can be made
to approach or recede from this diaphragm. The cap of the projection eye-piece
forms a diaphragm by which internal reflexion in the body-tube is entirely ob¬
viated. The aperture of this diaphragm is made to correspond with the greatest
aperture of the apochromatic lenses.

The projection eye-pieces are specially corrected for our apochromatic lenses
on the principle of the compensating series, but may, nevertheless, be
a d v antageously e m p 1 o y e d w i t h ordinary achromatic lenses of
large a p e r t u r e.

The designation of these eye -pieces corresponds, as in the case of the
other compensating eye -pieces, to those amplifications which they would yield
(magnifications being measured after the same principle as for the other compen¬
sating eye-pieces) if used for ocular observation.

The magnifications are 2 and 4 for the 160- mm tube, 3 and 6 for the
250-mm (10") tube.

We do not construct projection oculars yielding higher amplifications beyond
those indicated as these would not possess any practical advantage over the ordinary
compensating eye-pieces, which can be used when higher amplifications are required.

The magnification for any distance of image from the eye-piece is obtained,
by dividing this distance, expressed in millimeters, by the focal length of the
objective in use and multiplying the result by the number of the projection eye¬
piece employed. Thus the ocjective of 6 mm gives with the projection eye-piece 2
an image magnified 1000 times at, a distance of 150 cm, for

lbOO ^ 2 _ 1000

O

This rule holds good, strictly speaking, for long distances only; for short distances
the figure so obtained is in excess of the true value.

The image distance may be reduced in the case of 2 and 6 to about
400 mm and with 4 and 6 to about 250 mm (reckoning from the eye-piece) ; it
may, however, be increased to any desired length.

For further details see “Specialkatalog fur Mikrophotographie” (German).

Price of the Projection Eye-pieces: 40 Marks each.

10

Achromatic Objectives.

Respecting the general character of these objectives we refer to the
remarks on pages 2 and 4 — 6.

To the list of achromatic lenses only one new system has been added. At
the same time, however, most of the older types of achromatic lenses have been
reconstructed with a view to more completely eliminate imperfections
due to spherical and chromatic aberration than had been done
formerly or — rather — than could have been done without the aid of the new
glasses. With the dry lenses DD, E and F this improvement becomes obvious
by the clearer appearance of the image and the increased sensibility of
the lenses with regard to differences in the thickness of the
cover -glass and length of tube.

To the achromatic lenses enumerated in our last catalogue we have recently
added a water immersion lens of great focal length but having a relatively small
aperture, viz Objective D*. It is calculated to facilitate the examination at
medium magnifications (200 to 500 diameters) of living zoophytological objects
floating in water troughs. Its large focal distance gives to the microscopist
a relatively wide range in following the motions of these living objects. The
objective being constructed on the water -immersion principle, i. e. there being
always a layer of water interposed between the objective and the cover- glass,
the correction of the aberration will not be affected by focussing at various
depths of the water-cell, as to a diminution of the stratum of water under the
cover-glass always corresponds an increase of the stratum of the water above
the cover-glass, and vice versa. This manner of using the lens will, con¬
sequently, not interfere with the quality of the image. The relatively small
aperture is conditional to the great focal distance; for that kind of observation,
however, for which the lens is mainly designed this will, owing to the increased
depth, constitute rather an advantage than a disadvantage.

The system maybe used with or without cover-glass and gives equally
good images both with fresh and sea water.

<2ati Sjeioo, Optifcke OVezA-ftatte, ckna.

20

The magnifications yielded with this objective in conjunction with the
Huyghenian eye -pieces are the same as in the case of the D and DD ; when
used in combination with the compensating eye-pieces it gives nearly the same
magnifications as the 4-mm apochromatic lens of 0.95 aperture (about9°/0 less).

The Objectives a are simple achromatic lenses, so mounted that, notwith¬
standing their great focal length, the body of the microscope remains at its
ordinary elevation during observation. In Rj the thread is so placed that when
screwed home the lens is inside the body; it can, therefore, not be used
with a revolving nose-piece or other objective-changer. They are only intended
for use with the lower eye-pieces.

Objective a* consists of two achromatic lenses combined after a formula
peculiar to us. By means of a ring rotating like a correction collar the two
lenses can be approximated or withdrawn, whereby, using one of the lower eye¬
pieces, the magnification is changeable in the proportion from about 1 to 2. This
graduation of the magnifying power is obviously useful for many purposes.

We no longer supply the objectives BB, CC; G, K, L (water immersion)
and ]/8 and 1f18 (horn, immers.) of our former catalogues because their special
aim is now, in our opinion, better realised by the apochromatic lenses.

All objectives are also supplied adjusted for the 10-inch body and in
the English form of mount.

Regarding the use of achromatic objectives in conjunction with com¬
pensating eye-pieces it will be well to state here that only our achromatic
objectives from DD upwards, i. e. all those having relatively large aper¬
tures should be used in that manner. With those of small apertures the use
of compensating eye-pieces gives rise to similar errors (though of the inverse
chromatic order of succession) in the achromatism of the margin of the field
to those effected when apochromatic lenses are being used in conjunction with
the ordinary Ii u y g h e n i a n eye-pieces.

Separate mahoyany cases for objectives to be kept outside
the microscope case , with lock , according/ to size 7 to 30 Marks .

21

List of Achromatic Objectives.

...

De-

Numerical

Equivalent

Price

signation

aperture

focal length

without J with

correction

Marks

Dry Series

a,

—

40mm diVO

12 —

77 77

a2

—

35™ra (If")

12 —

7’ 77

a3

—

30mm

12.—

77 77

a*

—

38— 26mm (4"— 1")

40,-

7 7 7 7

aa

0.17

26mm (1")

27.—

7 7 77

A

0.20

18mm (f")

24 —

77 ' 77

AA

0.30

18mm

30.—

7 7 7 7

B

0.35

12mm

30. -

7 7 7 7

C

0.40

7“ (A")

36.—

7 7 77

D

0.65

4.3mm (i“)

42 —

7? 77

DD

0.85

4.3mm (}")

54— 74.

7 7 7 7

E

0.85

2.7mm (|")

66.— 86.—

77 77

F

0.85-0.90

1.85mm GV")

84— 104 —

D*

0.75

4.3mm (i“)

75.—

Water

Immersion

H

. J

1.15—1.20

1.15—1.20

2.4mm (TV0

1.8"'m (A")

110.— 130.—

144 — 164.

^Homogeneous

A

1.20

2.0mm (TV")

160 —

Immersion

4

1.30—1.35

2.0mra (Ty')

300.—

Cedar-wood oil, oz. bot. Mk. 0.75.
Cap bottles for immersion oil, Mk. 1.00.

Qati Sciii, Optifchc QVithjtattc, dcna.

Table of Magnification

of the Achromatic Objectives with the Huyghenian Eye-pieces

calculated for a tube-length of 160 mm and an image distance of 250 mm

Eye-piece : 1 2 3 4 5

at
a2
a3

a*
aa

A, AA
B
C

D, DD, D*
E
F

H
J

i

is

1 2 3 4 5

al

7

10

15

20

a2

11

16

23

30

a3

20

30

40

50

a*

4-8

7-14

10-20

15-30

aa

25

35

47

60

77

A, AA

37

50

70

90

115

B

60

85

115

145

185

C

105

145

200

265

325

D, DD, D*

175

240

325

420

540

E

280

390

535

680

865

F

415

585

790

1000

1275

H

320

440

610

770

985

J

430

585

810

1030

1315

i

is

385

530

730

925

1180

23

Huyghenian Eye-pieees.

We supply these for use with the ordinary achromatic objectives. Their
focal lengths and magnifications are shown in the following table.

Eye-piece No.

1

2

S

4

5

Focus in mm

50

40

30

25

20

(Eye-piece) magnification

3

4

5.5

7

9

Price 7 Marks each.

The magnification is computed by the same rule as in the compensating
series (see page 10), the varying position of their lower focal planes being,
however, taken into consideration.

With regard to the selection of eye-pieces for a microscope we would remark,
that all our achromatic objectives are capable of still giving effective magnifications
for regular observation with Ocular 4, good illumination being understood in the
case of the highest powers.

We no longer supply the “orthoscopic” eye-pieces of former catalogues, as
they are greatly inferior to the compensating and projecting oculars.

Respecting the use of Compensating Oculars with achromatic objectives
vid. p. 20.

We do not supply Huyghenian Oculars for the long (English)

tube.

Oculars for special purposes (Micrometer-, Spectroscopic and others) vid.
No. 28 — 30 and 52 — 55.

(Bail Seba, (Splifcfu fyCeififtatU, cJena.

Accessory Apparatus
for testing the fundamental properties
of Microscopical Objectives.

Maries

1

H Apertometer after Abbe, for estimating the numerical and
angular aperture of objectives (Journ. of the R. Micr. Soc., Jany.
1878, p. 19, and 1880, p. 20). For use on any large stand fitted
with a draw tube. Including the auxiliary objective, in case
(fig, 2) with directions .

GO.-

Fig. 2.
Apertometer.

2

The saime apparatus, glass disc, mounted on inetal plate
with a slot for the adjustment of the indices .

80. -

25

No.

Marks

3

*Test-plate after Abbe — for testing the spherical and
chromatic aberration of objectives, and for e s t i m a t i n g t h e
thickness of cover corresponding to the most per¬
fect correction. Six cover-glasses, having the exact thickness

Fig. 8.

Test-plate No. 3.

marked on each (0.09 to 0.24 mm), cemented in succession on a
slip, their lower surface silvered and engraved with parallel lines,
the contours of which form the test. For use with the Abbe
Condenser (see Instruction for use). In case .

10.-

Saif Sevas, £)pti (cfu fyVtzfaftatti, ekna.

Stands.

The general form of our stands, like most others of continental design,
originated in the type first introduced by Oberhauser and developed by Hart-
nack. It is more or less universally admitted that the size and general arrange¬
ment of this kind of stand best corresponds to the requirements of scientific
research. The extensive employment of the continental form even in English and
American laboratories, as well as the testimony of numerous competent investi¬
gators, shows that, for scientific work at least, they are preferred even there to
*

the more elaborate of the so-called English stands.

Latterly we have endeavoured to perfect the mechanical details of the
microscope, and have made several improvements in the three main directions,
which constitute the essentiality of the stand, viz. the stage arrangements,
the means for focussing and the illumination.

A. The Stage.

The dimensions of the stage in all our stands (except in the laboratory
stands VI and VII) are sufficiently large to allow of any size slip or cultivation
plate or dish being used.

The stage is provided with an opening of 33 mm (15/16") in the case of
stands I to V, in order that the large field possessed by the objectives of long-
focus (including the projection lens of 70 mm) may be fully utilized. It may, however,

be reduced to the diameter of the upper lens of the condenser, by inserting a
diaphragm provided for the purpose, in cases where very small slips are to
be used.

The height of stage is in the case of stands IIa to Y reduced to the
lowest limit which will admit of the adaption of the Abbe illuminating apparatus,
in order that the hands may be supported by the table when manipulating on the
stage. In the larger stands (I, P, photographic and mineralogical stands) the
stage is made higher, to facilitate the employment of various methods of illu¬
mination other than by the Abbe illuminating apparatus, which are occasionally
required.

Mechanism for moving the object is provided in I, P, IP, the large
Babuchin, photographic and mineralogical stands.

This consists of the following arrangements:

a) Revolution of the stage and body about the optic axis (stand I).

b) Revolving stage-plate with arrangement for centering (stands P , IP , large
Babuchin and mineralogical stands).

c) Mechanical stage (stand Ia and stand for “photo-micrography”). The one
adaptable to stand P possesses the general arrangement of the English form of
mechanical stage, and may be substituted in place of the rotating vulcanite stage-
plate. The micrometer stage of the photo-micrographic stand is made for delicate
adjustments of the object.

With stands I, IP, IV, V and the “Babuchin stand” the “adaptable
mechanical stage” recently constructed may be used; for very fine lateral
movements Stage Screw - micrometer N o. 31 may be used as a mechan¬
ical stage.

Mechanical stage movements were formerly peculiar to English micro¬
scopes and were rejected as objectionable by the majority of continental microscopists.
It is only of late years that they have received more attention on the continent
and for some years they have formed an object of experiment also in our works.
We have arrived at the conclusion that mechanical movement of the object is of
advantage in the following cases:

1) In the employment of high power lenses, when it is required to bring a
point seen at the margin into the middle of the field. This, as is well known,
when done by hand, is often a sore trial of patience. The small amount of move¬
ment necessary to accomplish this may be effected, to a certain extent, by the cen¬
tering arrangement of the revolving stages of stands Ia and IP (see above b).

2) For systematically searching a preparation.

3) For counting particles within a specified area of the surface of the
object.

(Bait Sctso, 0pli fc&e QVuti-ftatte, Sena.

28

4) For registering certain spots in specimens in order to readily find them

again.

5) For the projection of real images.

In cases 2 to 5 a mechanical stage like the one of stand Is , or of the photo¬
micrographic stand or the adaptable mechanical stage will be found a more or less
indispensible adjunct. These are all so constructed as not to interfere in the least
degree with any other manipulative process, and they may be retained in situ even
when using pure-cultivation plates. We consider this to be a great improvement
on the older form of mechanical stages, which must be removed from the stand
during certain investigations with the instrument.

If the divided scales, with which the mechanical stages are provided, are to
be used as means for refinding a particular spot of a specimen, the

following points should be observed :

a) In the case of the mechanical stage of stand Ia care should be taken that
in the interval between searching and refinding the centering screws should be
left in an unaltered position.

b) The small adaptable stage should remain in a fixed position or should
always be adapted to the stand in the same position (the small indentation produced
by the fixing screw may be used for this purpose).

c) In both cases the slip should be accurately brought into its original

position.

If it is desired to mark a specimen in such a manner that a particular spot
may without difficulty be found by different observers using different instruments at
different places, the best plan would be to mark any part of either the slip or the
preparation itself in a conspicuous manner, say by means of a diamond cross, and to
note the exact distance in both coordinates of the particular spot which is to
be refound from that mark. The second observer will, in proceeding from this mark,
have no difficulty in refinding the desired spot by means of his mechanical stage.

As a matter of course , a lower power should be used to refind a spot

and bring it into the centre of the field previous to examinations with a high
power lens.

B. The Adjustment of the Objectives.

The coarse adjustment. Whilst the coarse adjustment, in its form by
means of sliding tube as retained in the cheaper stands V, VI and VII, has
undergone scarcely any alteration since its introduction, the rack and pinion
motion of all the other stands has already some years past been very consider¬
ably improved by us. We have constructed special machines for the accurate
production of the (diagonal) gearing, and this motion is now made so perfect that
objectives of medium power can be focussed by it alone without recourse being
had to the micrometer screw.

29

Tlic line adjustment. This also lias during the last years received our
special attention. The result of our efforts is the *Micrometer movement
of new construction now fitted in all our stands except No. IX. (For detailed
description see Zeitschrift fur wissenschaftl. Mikroskopie, III, p. 207, 1886.) The
superiority of this new arrangement is mainly due to the force exercised by the
micrometer screw being transferred to the moveable limb by a single contact
between hardened steel surfaces. This ensures an extremely delicate and uniform
motion of the limb carrying the tube.

The divisions on the milled head of the micrometer screw in stands
I — IV furnish a means for exactly registering the vertical movements of the tube.
In the new stands each division corresponds to 0.01 -mm elevation or depression
of the tube in the direction of the optic axis.

By this means measurements of thickness may be made with some
degree of accuracy. The upper and lower surfaces of the object are successively
focussed and the amount read off on the milled head by the fixed index. In doing
this it must be remembered to make both adjustments by a rotation of the screw
in the same direction. The depth of layers of air is then equal to the differ¬
ence between the two readings.

The thickness of layers of any other substances may also be measured by the
same arrangement. Estimation of the thickness of cover-glass for instance is best
done as follows: With a medium-power dry lens (D or E) and eye-piece 3 or 4,
using central illumination focus the upper and lower surfaces of cover-glasses of exactly
known thickness — e. g. the covers of an Abbe test-plate — and note the appar¬
ent thickness so obtained. A comparison of this with the known true value
gives, once for all, the coefficient for reducing measurements, made with the
same objective under precisely similar conditions, of any other covers to their true
values. Roughly speaking this equals 3/2 or more exactly 1.52 (the refractive index
of glass). The thickness of sections is estimated in a similar manner.

The medium tube length of our stands is 160 mm from the attachment
of the objective to the upper end.

The draw-tube arrangement which is possessed by all stands with the ex¬
ception of stand IX and the small stand for mineralogical purposes, admits of the
tube-length being increased or diminished. With stands I to IV the length of
the tube may be read off by means of a millimeter scale worked upon the tube.
The lower end is tapped with the standard thread to take the auxiliary objective
used with the apertometer.

The inner diameter of our draw-tubes is 23 mm at the upper end.

QazA 2>ei«, 0p tv|cHe ckna.

30

C. The Illumination of the Object.

The modern microscope is essentially constructed for illumination with trans¬
mitted light. Ordinary microscopic observation demands exclusively illumination
by white (day or lamp) light without limitation of the field, but the incident
pencil should be capable of wide variation as regards its angular aperture (wide
or narrow illuminating cone) and its direction (central or oblique light). These
requirements are fulfilled by the ABBE Condenser, first introduced by us in 1873
(Max Schultze’s Arcliiv f. mikr. Anatomie, IX, p. 413, 1873), and now so gener¬
ally employed and so universally acknowledged as an indispensable accessory in
advanced microscopic work, that it forms an essential adjunct to
intended for scientific research. For description vid. Nos 17 to 20 of this
Catalogue.

To facilitate the employment of the cylinder diaphragms, which in our
older stand necessitated the removal of the whole illuminating apparatus previous
to their insertion , we have a few years ago made certain alterations in the
mechanical arrangement of the Abbe illuminating apparatus, which, at the same
time, render the frame of the apparatus available for the adaptation of other
illuminators, such as the special ones described in Nos 20 — 23.

31

All the large and medium size stands are supplied in solid mahogany
upright cases. This form is admittedly much the more convenient and certainly
deserves preference to the flat cases, as it allows of the instrument being taken
out and replaced without risk of any of its fittings being thereby deranged. The
size is reduced as much as possible for the sake of compactness, but sufficient
room is provided for the instrument with its objectives (and nose-piece) and eye¬
piece in situ and for an ample assortment of objectives, eye-pieces and usual
accessory apparatus.

Stands VI, VII and IX are supplied, as in former years, in flat mahogany
case s.

The cases are furnished with the following appendages:

Metal name plates, including engraving, to screw on the door, M. 5.—.

Leather travelling cases according to size M, 18.— to 30,—.

The ordinary cases are included in the price of the stand. Cases of parti¬
cular design, walnut, ebony etc., are supplied at proportionate extra charges.

QaxX Shua.

Specification and Price
of the various Stands.

No.

4

A. Large Stands.

Stand I. Inclinable from strictly vertical into strictly hori¬
zontal position and fixable in any inclined position by a clamping
lever; square vulcanite stage 100 X 100 mm (4" X 4"), stage
and body admitting of rotation about the optic axis.

Coarse adjustment by rack and pinion, fine adju st¬
ill e n t by micrometer screw with divided head.

Draw-tube with millimeter scale.

Abbe illuminating apparatus No. 17 with rack and pinion
adjustment. Iris diaphragm of the newest construction (with
full aperture). Condenser system of 1.40 apert. interchange¬
able with cylinder diaphragm which may be added at an extra
charge of M. 7. — at any time (Fig. 4) .

Marks

300.—

The prices of stands do not include any optical or mechanical parts beyond
those enumerated in the above specification. Suitable combinations are com¬
piled at the end of the catalogue.

33

Qatl OftifJvc WttlfiUU, Sena

No.

Maries

5

Stand k Stage with rotating vulcanite disk of
abt. 4 3/4" dia. (120 mm), which is removable and can at any time
be replaced by the mechanical stage (Price M. 100. — )
described below. The rotating disk may be accurately
centered by means of two milled-head screws. This adjust¬
ment also serves to give slight motion to the object in the
absence of the mechanical stage.

In all other respects exactly as stand I (Fig. 5).

Without mechanical stage . 300. —

With mechanical stage capable of a movement of 18 mm

in either direction and rotating vulcanite disk . . . 400.—

For our mechanical stages we claim the following advantages
not possessed by those made by others in former years:

1. They permit of the use of slips of any size. Cultivation
plates or dishes may be placed upon the stage by removing the
clips and milled heads, which is very easily done.

2. They are provided with two vernier scales, admitting of the
position of a point being read within a l/10 mm. When using this
arrangement the slip should always be pushed against the projection
at the left hand of the object holder, so that it always occupies
the same position in relation to the movable slide of the stage. The
divisions can be used for measurements, if the accuracy required
does not exceed 0.10 mm.

3. The stage is available with any method of illumination.

Attachment of the mechanical stage is effected in the simplest
manner by loosening the centering screws, compressing the counter¬
spring, removing the rotating disc and substituting the former by
the reversed manipulation.

The prices of stands do not include any optical or mechanical parts beyond
those enumerated in the above specification. Suitable combinations are com¬
piled at the end of the catalogue.

35

36

No.

Maries

6

Stand for Photo-micrography. Square stage, 100x100
mm (4" X 4"), with mechanical stage for imparting delicate move¬
ments to the object-slide, which may be of any size (inch cultiv¬
ation plates).

Body very short and of great diameter, so that photographic
objectives of very long focus (projection system 70 mm) may be
used w i t h i n i t.

In all other respects similar to stands I and I*.

This stand may, with good advantage, he used for usual
ocular observation.

For the purposes of photo-micrography it is advisable — and
for all advanced work necessary — to substitute for the usual
condenser of 1.40 aperture the achromatic centering con¬
denser of 1.0 aperture, price M. 75. — (No. 20). This condenser
may, naturally, be used for ocular observation as well.

The mechanical stage of the above stand is constructed
with a view to imparting such a very slow motion to the object
as the projection of a magnified image at a great distance ne¬
cessitates. Whilst the revolution of the object is effected in the
ordinary way by turn-table rotated by rack and pinion, the cross
motions are obtained by two sliding-pieces mounted at right angles
to one another and actuated by micrometer screws. Vernier reading
to 0.10 mm as in stand Is.

With Abbe illuminating apparatus No. 17 with ordinary (non-

achromatic) condenser of 1.40 apert .

Achromatic centering condenser No. 20 .

Or id. non -centering and without iris diaphragm, inter¬
changeable with the usual condenser .

350-

75.—

45 —

The prices of stands do not include any optical or mechanical parts beyond
those enumerated in the above specification. Suitable combination s are cmn-
jriled at the end of the catalogue.

37

QcLZ/t y cJchcv,

B. Stands of Medium Size.

No.

7

Maries

Stand lla similar to Ia, stage with revolving vulca¬
nite disc of 100 111111 (4") diameter, which is centered by two
milled-head screws and counter-spring and, within small limits,
can be used as a tine stage movement.

Coarse and fine adjustments as in the preceding
instruments.

Abbe illuminating apparatus No. 17 with iris diaphragm
and condenser system of 1.40 mini, apert. (Fig. 7) .

290.—

The prices of stands do not include any optical or mechanical parts beyond
those enumerated in the above specification. Suitable combinations are com¬
piled at the end of the catalogue.

39

Stand IK (7« ful1 size*>

Gart %ev>$,

©ptvfcfve ^Vt^tatU, Sena.

40

No. |

8

Stand IV*. Inclinable, without clamping lever. Fixed
stage, 90X90 mm (3 1 / 2 X

Coarse and fine adjustments as above.

Abbe illuminating apparatus No. 17 with condenser
system of 1.20 num. apert. Cylinder diaphragm to fit in place of
the condenser (M. 7.-). Without iris and cylinder diaphragms,
which, however, may be added at an extra charge of M. 15.—
and M. 7. — respectively, at any time (fig. 8) .

Maries

200.—

9

Stand IVb similar to IVa but without illuminating
apparatus. This is replaced by the ordinary plane and concave
mirror with universal motions and the ordinary cylinder dia¬
phragm which is fixed to the under surface of the stage by a
bayonet joint. This arrangement permits of a rapid interchange
of the diaphragm for the simplified Abbe illuminator No. 18, price
M. 40. — (condenser system of 1.20 num. apert, with fixed iris

diaphragm) .

Stand IVb inch illuminating apparatus No. 18 .

150 —
190 —

The prices of stands do not include any optical or mechanical parts beyond
those enumerated in the above specification. Suitable combinations are cam-
piled at the end of the catalogue.

41

Qa*t Seiw, 0ptif4ve ^Viz^tatU,

cJena.

4 2

No.

10

Maries

Stand Va. Inclinable, fixed stage 90X^0 mm (31/2X31/2/0-

Coarse a d j u s t m e n t by sliding tube.

Fine adjust in e n t by micrometer screw.

The lower body of the instrument, including the Abbe illu¬
minating apparatus, identical to that of stand IVs (without iris
and cylinder diaphragms which may be added at any time at an
extra charge of M. 15. — and M. 7. — ). (Fig. 9) . 120. —

11

Stand Vb. Similar to the above, but without the Abbe illu¬
minating apparatus. Other arrangements as in stand IVb . . .

Stand V1’ with illuminator No. 18 .

95.—

135.—

12 Babuchin Stand. This instrument, made after the design of

i

Prof. Babuchin of Moscow, is included in the series of our stands
as it possesses several novel features of practical value which
cannot be combined in the ordinary form of stand.

These are substantially as follows:

1) The Abbe illuminating apparatus is constructed in a manner
resembling that adopted by Nachet. The condenser system mounted
in a sleeve may be inserted from above in the carrier which
can be screwed do w n w a r d s and s w ung out to the 1 e f t.
By these means the condenser system is easily changed for another
of different aperture, or for a cylinder diaphragm or polariser.

2) Below the condenser carrier is a sliding piece admitting
of a rotation about the optic axis, in which the iris diaphragm
may be inserted and placed in any excentric position for oblique
illumination.

■>) The illuminating apparatus is moved along the optic axis,
not, as is generally the case, by rack and pinion, but by a screw
fitted to the under side of the stage on the left hand, which gives

The prices of stands do not include any optical or mechanical parts beyond
those enumerated in the above specification. Suitable combinations are com¬
piled at the end of the catalogue.

43

Fig. 9.

Stand Va. (*/2 full size.)

Qazi Sciii,

Optvfc he ^IVczfi^tatti, dena

44

a slow and more delicate motion. When the screw has been
turned until the condenser has reached the lowest point, a further
turn of the screw causes it to turn out automatically to the
left, in which position the condenser system can be changed or
centered.

A specially large mirror fixed to a sliding holder allows of
a wide range of up and down movement, and, when the condenser
is swung outward, can be placed in any oblique position.

The condenser has an aperture of 1.40.

In accordance with the wishes of Prof. Babuchin we make
two models of this stand.

a) Large BABUCHIN Stand, with rotating and centering
stage (similar to stand IT1). The whole body of the stand is
attached by a hinge joint to a prism-shaped pillar sliding in an
outer tube, so that it can be withdrawn and fixed by a clamping
screw. This arrangement admits of a compact form being given
to the instrument and of an increase to the height of the stage
and stand generally, should this be required for the application
of a photographic camera, the insertion of some larger substage
apparatus etc.

The height of the stand may be thus varied from a minimum
of about 200 mm, with a body-length of 100 mm, to a maximum
of 230 mm ; that of the stage from 105 to 135 mm. — This stand
is fitted with the new micrometer fine adjustment (Fig. 10) . .

b) “Student’s Microscope” after Babuchin — which has
the same upper body as its predecessor; it is, however, not in¬
clinable, does not admit of the variation of the height of the
stage and is provided with a somewhat simplified illuminating
apparatus, which does not allow of the iris diaphragm supplied
with the stand being rotated or placed in an oblique position ; it
is, however, provided with a condenser of 1.40 aperture . . .

Marks

320 —

200.-

45

Fig. 10.

Babuchin Model Staud. (//3 full size.)

Car-f 2vt35, 0pti ^-fvc eliJtta

40

C. Small Stands.

No.

13

Marks

Stand VI. Fixed stage 60X70 mm (2 Va X23/4//)*
Illumination by plane and concave mirrors with universal mo¬
tion. Cylinder diaphragm with jacket fitted to the under surface
of the stage by a bayonet joint; easily removed when very oblique
light is required. This arrangement also permits of the illuminator
No. 19 (of about 1,0 num. apert.) being inserted in place of the
diaphragm.

Coarse adjustment by sliding tube. Tube fitted with
draw-tube.

Fine a d j u s t m e n t by micrometer screw of new con¬
struction.

This stand is made to incline (Fig. 11) .

65.—

Stand VII. In all respects as stand VI but not inclinable.
Substantially built for laboratory use. (Illuminator No. 19 appli¬
cable as in stand VI). (Fig. 12.) .

The extreme care exercised in the construction of the micro¬
meter adjustment of stands VI and VII renders them available for
use with the highest dry powers. For immersion systems these
stands cannot fairly be expected to be rigid enough, though, if
particular care be taken even these lenses may be used in excep¬
tional cases.

GO.—

Stands V, VI and VII cannot be subsequently fitted with
rack and pinion adjustment in lieu of the draw- tube arrange¬
ment. All those who wish to spend a certain sum in making a
first purchase with the intention of later on adding an immersion
lens without having to undergo any extra-expenses occasioned by
deficiencies in the stand, are therefore strongly advised to select
one of the larger stands, i. e at least IV.

The prices of stands do not include any optical or mechanical parts beyond
those enumerated in the above specification. Suitable c o nib in at i o n s are com¬
piled at the end of the catalogue.

47

Fig. 11.

Stand VI. (Half size.)

Fig. 12.
Stand VII.

(2 art Sevas,

0ptifcfve ftatte, 3eua

48

No.

15

When using a revolving nose-piece with these smaller stands
a clamping ring (ffl. 5. — ) will be found convenient ; this pre¬
vents the tube from sliding down in consequence of the weight of
the nose-piece and the objectives attached thereto.

The sliding objective-changer No. 25 is not appli¬
cable to stands VI and VII, owing to the small distance between
the tube and the stage.

Stand IX. Simple stand for laboratory and technical purposes.

Plain large stage of 100 mm (4") dia. with large aperture, which
may be decreased if required by dropping in a diaphragm.

Large plane and concave mirrors.

Adjustment by rack and pinion, the construction of which
still admits, however, of the use of medium powers (C, D). (Fig. 18.)

Recommended by Prof. Johne (Veterinary School, Dresden)
for the detection of Trichina (M. 70. — incl. objective and 2 eye¬
pieces).

Fig. 14. Hand Microscope.
(Vs full size.)

16

Hand Microscope for demonstration in classes. Stage with
clips to hold the specimen; sliding tube, which after adjustment
is securely fixed by a clamping ring. Fine adjustment may be
effected by altering the position of the eye-piece. In use it is
directed by hand towards a window or lamp. Available even with
objective D. Without objective, eye-piece and case (Fig. 14). .

Marks

40-

15-

49

(V, full size.)

(Barf Oyttfche ^IVeiyk^tatte, Sena

50

No.

Stands for crystallographic and
petrological researches.

A. Large Stand (Fig. 15).

Similar to stands I and Ia in form and size.

Horse-shoe base; inclinable body.

Coarse adjustment by rack and pinion G.

Fine adjustment by means of micrometer screw with divided
bead M.

Abbe illuminating apparatus, adjustable by rack and pinion
W with condenser system C of 1.40 aperture mounted in sleeve
and interchangeable for cylinder diaphragm (M. 7. — ) or any of
the apparatus No. 20 — 23. Diaphragm carrier with iris diaphragm,
adapted for insertion of central stop diaphragms, mica and selenite
films or polariser (Nicol) P; arranged to admit of rotation
about the optic axis, of being placed obliquely and of being entirely
swung out of the axis round the pivot f (vid. Fig. 15 and 16).

Rotating stage with divided circle at circumference and cross-
lines at right angles to one another.

The draw-tube is provided with a mm-scale and separately
adjustable by means of rack and pinion g and carries at its
lower extremity an Amici (Bertrand) lens P, which may be in¬
serted through an opening in the outer tube ; at the upper end it
is fitted with a divided circle for polariscopic measurements. The
tube is provided at its lower end with Biot-Ivlein’s quartz plate
K and centering arrangement c c for the objectives.

With condenser of 1.40 ap., iris diaphragm, polariser, analyser,
Klein’s quartz plate and Amici lens.

Maries

550-

Fig. 15.

Large Mineralogical Stand (half size).

< Saz'C Optvf’cfve tyXhz&^tatfa, 3ina.

Marks

B. Medium Stand (Fig. 16).

This stand is similar to the preceding one, but smaller in
size, which corresponds with that of our stand IV. It is inclinable,
is fitted with the same arrangement of the illuminating apparatus,
the stage, the coarse and fine adjustment of tube, the fittings for
Klein’s quartz plate and the analyser, and has the same centering
objective-holder. It is, however, adapted for the eye-piece
No. 50 for the observation of axial images and is supplied
without the Amici lens.

With condenser, polariser, analyser, Klein’s quarz plate

The following special illuminating apparatus may be used with
these two stands, viz :

No. .21, Illuminating apparatus for monochromatic light

after Hartnack .

No. 22, Micro-spectral objective after Engelmann . . .

No. 23, Spectro-polariser after Rollet .

These may by means of the centering collar supplied with
them be fixed and adjusted in the sleeve of the condenser system
by the observer.

350.—

80.—
124 —
240 —

53

Fig. 16.

Mineralogical Stand. Medium size.
(V2 full size.)

Qazt Sxsico, 0pti/fcac tyViififtatU, dcna

54

No.

C. Small Stand (Fig. 17).

#

Marks

This stand is in form and size similar to the tripod stand IX.
Not inclinable. The polariser is mounted together with a con¬
denser of 1.0 aperture in a sleeve and may be rotated about the
optic axis by means of the lever a. After having drawn the po¬
lariser down within the sleeve a short distance (so as to bring
the condenser under the underside of the stage), it may be swung
out of the optic axis by means of the lever b. The polariser may
also be entirely withdrawn and substituted by the ordinary con¬
denser or a cylinder diaphragm, but none of the special illuminat¬
ing apparatus adaptable to the two stands A and B can be used
with this stand.

The large double mirror (plane and concave) is movable
in all directions and can be easily withdrawn as in the larger
stands.

The stage is arranged to rotate and is provided with a
divided circle.

The tube is fitted with rack and pinion adjustment G. This
mechanism is, however, so carefully fitted that by its means even
the medium powers (C, D) may be conveniently focussed. The upper
end of the tube is fitted with a divided circle T for analyser A and
the lower part with the centering collar c c, Klein’s quartz plate
K and a small shutter to close the aperture occupied by the
quartz plate when this is not being used.

With polariser, condenser system, analyser and Klein’s quartz
plate .

Condenser system of 1.0 ap., without polariser, with small
iris diaphragm .

Cylinder diaphragm .

180.—

22.—

7,-

*

55

Fig'. 17.

Miueralogical Stand. Small size.
(Vs full size.)

<Sai/C Sevas, t£)p(‘i|'ctte . ^C^eafij’lattc, cletia

No.

Maries

We supply the following

Accessories and auxiliary apparatus for petrological

researches.

Huyglienian eye-pieces 1 to 5 with crossed lines . . each
BERTRAND’S eye-piece (with quadruple quartz plate) . .

Stauroscopic plate .

Micrometer eye-piece No. 28 .

Screw-micrometer eye-piece No. 30 .

Goniometer eye-j>iece No. 40 .

Eye-piece for the observation of axial images No. 50
(for the medium and small stand) .

Spectroscopic eye-piece No. 53 .

Micro-spectro-photometer after Engelmann No. 54

ABBE camerae No. 43 and 44 . M. 30. — and

Set of 8 selenite and mica films after Mohl .

Respecting the appliances for photo-micrography and for the
projection of objects in general and of axial images in particular
we refer to pag. 92.

Analyser for projection (made to screw to the projection

eye-pieces).

10.—

35.—

7.—

15.—

60.—

30.—

30.—
165.—
480.—
42. —
10. —

20. —

Illuminating Apparatus.

A. For white light.

No.

17 ^Illuminating Apparatus after Abbe (new arrangement).

The essential feature of this is a condenser system of short
focus, which collects the light reflected by the mirror into a cone
of rays of very large aperture and projects it on the object.

The full aperture of the illuminating cone should only be used
when finely granular and deeply stained particles (bacteria) are being
examined with objectives of large aperture. In every other case
the cone must be reduced to suitable dimensions either by an iris
diaphragm (see below) or common diaphragm (central illumination).
On placing the diaphragm excentrically , by means of the rack
work attached to the carrier, the central rays are excluded, and a
certain extra-axial portion of the illuminating pencil falls upon the
object (oblique light). When the diaphragm is thus excentrically
placed this oblique pencil can be directed from all azimuths by
rotating the carrier round the optic axis.

The central stop diaphragm shuts off all the axial and trans¬
mits only the marginal rays (dark-ground illumination; see special
instructions).

Maries

S az-C SSeioo, <£)p tifcfic °ICkzdt(tdtte, dina.

58

Fig-. 18.

Abbe Illuminating apparatus.

a) Condenser system of 1.20 num. apert., b) condenser system of 1.40 num. apert., c) cylinder
diaphragm, d) iris diaphragm, e) milled head for throwing the diaphragms out of centre.

No.

The Condenser system — made as before in two forms,

a) a double combination of 1.20 num. apert., and

b) a triple combination of 1.40 num. apert.,

is mounted in a holder which tits a sprung jacket on the apparatus.
This arrangement facilitates an interchange of the two condenser
systems, and also serves to carry the following apparatus when
the condenser is not used :

c) the ordinary cylinder diaphragm;

Marks

I

59

cl) the illuminating appliances described under
Nos. 20—23.

Maries

The centering collars required for the adjustment of the illu¬
minators 20 to 23 are now supplied with these and are included
in their prices.

c

Fig. 19.

Centering Collar.

e) Centering collar for accurately adjusting achromatic or
apochromatic objectives used as illuminators in photo-micrography.

As most of these appliances require adjustment to the plane
of the object, every Abbe illuminator now made is fitted with
rack and pinion for adjustment in the direction of the optic axis.
Every microscope fitted with it may, therefore, be used in con¬
junction with any other form of illuminator which
may be required.

(2 <xti 0-ptvfcA.e c Jena.

60

Marks

1) The iris diaphragm (Fig. 20), which is now included
in the Abbe illuminator, is a very convenient substitute for the
ordinary interchangeable diaphragms, as it affords a ready means
of gradually increasing or diminishing the aperture with the
greatest precision. Smallest aperture about 0.5 mm, largest — in
the newest form — equal to the full aperture of the
condenser system, so that it may remain in situ
when either the central spot diaphragm or polari¬
se r is in use.

Fig. 20.

Iris diaphragm.

The iris diaphragm may readily be adapted at any time
to any of our recent stands provided with the large Abbe illu¬
minating apparatus (i. e. I to Va). It is only necessary to remove
for this purpose the small screw which fixes an annular cap upon
the diaphragm carrier and, after removing this cap, to insert in its
place the iris diaphragm, which may then be fixed by means of
that small screw.

We do not supply the large ABBE illuminating apparatus
in a detached state, as in most cases considerable trouble and
annoyance is caused by having it fitted to stands of a differ¬
ent make, it being besides in many cases an utter impossib¬
ility to do so.

Our own stands, from I to IVa and Va are fitted with
this apparatus, viz stands I, Ia, IIa and the “photo-micrographic”
stand with a condenser system of 1.40 num. apert. and iris

61

diaphragm; stands IVa and Va with a condenser system of
1.20 apert. but without iris diaphragm. The cylinder
diaphragm for these stands will, in future, only be supplied if
specially ordered and charged for separately. It is gauged to
exactly lit in all cases the sleeve of the condenser system.

The following separate parts of the illuminating a p p a -
rat us No. 17 may he supplied singly:

a) The double condenser system of 1.20 apert .

b) The triple ,, ,, of 1.40 apert .

Both fixed in their mounts without jacket; with jacket
the price is M. 5. — more.

c) The cylinder diaphragm — cylinder with three stops . .

d) Nos 20 to 23.

e) Centering collar .

f) Iris diaphragm .

^Simplified Illuminating Apparatus for the stands ivb
and V'1. Condenser system of 1.20 num. apert. with iris dia¬
phragm (not adjustable excentrically) ; giving, therefore, central
illumination in any degree, but not oblique. Fitting the sleeve
fixed at the underside of the stage of the stands IVb and Vb,
having simply to be substituted for the cylinder diaphragm . .

Illuminating Apparatus for the stands VI and I’ll. Con¬
denser of 1.0 num. apert. to be inserted in place of the cylinder
diaphragm. Without diaphragms. The gradation of the (central)
illuminating cone is effected by sliding the system in its jacket

or, in a better way, by the

(Small) Iris diaphragm for the illuminating apparatus No. 19

Numbers 18 and 19 may be ordered at any time by
possessors of the corresponding stands, as they are made
to fit these without any alteration. For fitting an iris
diaphragm subsequently ordered to a condenser No. 19 it
will be necessary to have the latter sent to us.

Maries

20.—
25 —

7.—

20-

15.

40-

10.—

12 —

Gaz-C Zeiio, Gpti fcfu fyVezfi jtatti, 3 e na.

62

No.

20 Centering achromatic Condenser. Specially adapted for
the requirements of photo-micrography, viz for projecting
a sharp image of the source of light in the plane of the object.

Fig. 21.

Centering achromatic Condenser.

Achromatic condenser of 1.0 num. apert, with iris diaphragm and
centering adjustment. Made to fit the sleeve of the Abbe illu¬
minating apparatus into which it may be inserted (from above)
in place of the ordinary (non-achromatic) system (No. 17 a or b).
Focussing effected by means of the rack and pinion adjustment of
the Abbe illuminating apparatus .

20a

Achromatic Condenser without, centering adjustment and
also without iris diaphragm. Similarly adaptable as No. 20, but
to be used with the stops forming part of the diaphragm carriers

Marks

75.—

45 —

63

B. Illuminating Apparatus
for speetroseopieally decomposed light.

No.

When it is required to illuminate a portion of an object in
the field of the microscope with a single pure spectral colour or
to observe the effect of the whole spectrum upon it, or finally
to study the effects of the spectrum of polarised light, the instru¬
ments Nos. 21, 22 or 23 have to be used. These are connected
to the Abbe illuminator by the centering collar supplied with
each instrument (vid. Fig. 23, p. 64) and adjusted to the object
plane by the rack and pinion motion of the illuminator. All three
instruments necessitate, unless used with either stand I
or Ia, an inclined position of the stand.

Marks

Fig. 22.

Illuminating apparatus for monochromatic light.

21

Illuminating Apparatus for monochromatic light after

HARTNACK. The light which emerges from the slit Sp is rendered
parallel by means of the collimator lens (7, is then spectrally
decomposed and projected upon the specimen by means of the
projection objective 0. The spectrum is sufficiently extended to
ensure approximately uniform monochromatic illumination witli
higher powers. By adjusting the position of the slit by means of

(Past Swisa, 0pti Sltkr fi ^taMe, ckna.

64

No.

screw sx the various colours of the spectrum may be made to
successively traverse the field of vision. The screw s2 serves to
regulate the width of the slit .

Maries

80.—

Fig. 24.

Micro-spectral Objective.

22

Micro-spectral Objective after Engelmann, for observ¬
ing and measuring the effect of the colours of the spectrum on
microscopical objects (Botanische Zeitung, 1882, No. 26; Pfluger’s
Archiv, Bd. XXVII, p. 464, Bd. XXIX, p. 415). Slit mechanism,
collimator lens, Amici prism and projection objective are com¬
bined in a tube about 77 mm in length, which fits below the stage
concentrically with the axis of the microscope so as to project a
real spectrum upon the preparation under observation. The edges
of the slit are moved symmetrically by a screw with right and
left hand threads, so that the middle of the slit remains stationary ;
the divided head of the screw indicates the width of the slit as
adjusted in 100,hs of a millimeter; the length of the slit may be
regulated on both sides by two slides acted upon by screws. —
Ordinary objectives are used for projecting the spectrum, viz,
according to the desired size of the spectrum, either A, B, C
or D, which by the narrow gauge thread of the lens mounts may
be screwed to the instrument just above the Amici prism. (Fig. 24.)

124.—

Fig. 25.

Spectro-Polariser.

Qazi ©pti jcHi ^IViz^tatti, 3t na

66

No.

23 Spectro-Polariser after Rollett (Zeitschrift fiir Instru-

mentenkunde, Jahrg. I, p. 366) as modified by Dippel, for deter¬
mining the character of double refraction in microscopical speci¬
mens for particular wave lengths. Combination of two flint-glass
prisms PP, arranged to produce a deviation of 90°, having on
one side a movable slit Sp and a collimator lens (7, on the other
(at 0) a microscope objective which, from below, projects a real
spectrum on the specimen under observation. Scale tube Sk
on the prism casing, with mirror, collimator lens and a scale
divided and numbered according to the wave lengths ; by reflexion
from one surface of the prism a real image of this scale is pro¬
jected together with the spectrum into the plane of the object.
The edges of the slit are moved symmetrically by a double
threaded screw so that the centre-line of the slit remains station¬
ary. A Prazmowski prism To mounted on a movable arm k in
front of the slit serves as a polariser, and between it and the
slit is a revolving ring 6r serving to receive selenite films for
producing interference lines in the spectrum. An A, B, C or D
objective is used to project a spectrum of the desired dimension
and is screwed to the prism case by the narrow gauge thread on

the lens mount. (Fig. 25.)

*• . v

This apparatus is arranged to connect with the frame of the
Abbe illuminating apparatus by means of the centering adjustment
supplied with the former. The adjustment in a vertical direction
is eifected by means of the rack and pinion, while the transverse
adjustment of the spectrum is obtained by the centering collar.

Including two selenite films for red of the second and third
order .

Marks

240.—

(

Appliances for changing
the objectives on the stand.

No.

Maries

These contrivances are required to satisfy two conditions :
1) that the image should not disappear on changing the objectives,
so that only a touch of the micrometer screw is necessary for
perfect adjustment, and 2) that the centering should be good,
i. e. that the same spot in the specimen remains in the field after
changing the lens.

The first condition is satisfied by adjusting the lengths of
the funnels of the objectives which are required to be inter¬
changeable in such a manner that on changing them their foci
may lie at a corresponding distance from the plane of the object1).
The second condition can only be realised in the ordinary “re¬
volving” nose-piece if this is specially adjusted for the particular
objectives intended for use with it. It is impossible, therefore,
to be answerable for the exact centering of nose-pieces sub¬
sequently supplied. To avoid this inconvenience we have lately
constructed the Sliding Obj ective- changer (see below)
which possesses special means for centering and can, therefore,
be adapted to any objective.

*) This applies to the achromatic lenses A to P on the one hand , the
apochromatic lenses 16-mm to 3-mm (ap. 0.95) on the other. Lens ax cannot be
used with any objective-changer; objectives a2, a3, a* and aa can be used with
objective-changers on those of our stands which are fitted with rack and pinion
adjustment.

Gatf Sibo, 0pti jAhe ^IVci-hftciltc, 3c na.

No.

24

68

Marks

Revolving Nose-pieces.

a) Revolving nose-piece for 2 objectives, (Fig. 26.)

20.—

Fig. 26.

Fig. 27.

Revolving Nose-pieces.

b) Revolving nose-piece for 3 objectives. (Fig. 27.) . . . 27.—

c) Revolving nose-piece for 4 objectives . 35.—

25

"Sliding Objective-changer. This apparatus is so ar¬
ranged that eacli individual objective can be centered and it
permits the use of any number of glasses. (Fig. 28 and 29.)

It consists of:

a) The tube-slide. This is screwed on the end of the body
like an ordinary nose-piece w i t h the slide opening t o w a r d s
the front. The plane of the sliding motion is not made at
right angles to the optic axis but inclined at a small angle to it.

b) The objective-slide. The plane of the slide is inclined
to the axis at an angle corresponding to that of the tube-slide,
so that the objective rises on being withdrawn and cannot damage
the specimen. At one end of this fitting is a screw turned by a
watch-key which acts as a stop in bringing the objective always
back to the same position and also serves as a centering ad¬
justment in the direction of the slide, while the adjustment in the
transverse direction is effected by a similar screw working at
right angles to the first.

69

Fig. 28.

Fig. 29.

Sliding Objective-changer.

Maries

Objectives whose settings are so matched that they are ap¬
proximately in focus when changed can, by means of the clamping
screw on the objective slide, be focussed accurately and then
fixed once for all in their proper position. The two pieces fit one
another accurately; any number may be supplied with the tube-
slide in the first instance or subsequently.

On changing the objectives with a properly adjusted changer
the same part of the object always occupies the field, the object
being so nearly in focus that only a slight adjustment by the
micrometer screw is necessary.

Tube-slide .

Objective slides, each .

We supply special cases for these changers, viz:

a) Case for 3 objective-slides .

b) h m 6 i j n .

10.—

10.—

4.—

7.—

(Bazt cbna.

Apparatus for measuring
and counting microscopical objects

A. Measuring Apparatus.

No.

26

With regard to measurement of the thickness of micro¬
scopical objects see p. 29.

Marks

The following instruments are intended for measuring the
length and breadth of microscopical objects.

Stage Micrometer.

a) One millimeter divided into 100 parts ; mounted on a glass

slip, in case .

b) Ten millimeters, the last being divided in tenths . . .

These serve merely as standards of known value

for determining the micrometer value of the meas¬
uring instruments proper.

Other divisions on application.

Vide also Nos. 36 — 38.

10.-

6.—

Eye-piece Micrometer.

27

Eye-piece Micrometer. Arbitrary divisions on a glass disc
to drop into the eye-piece ; for measuring the magnified image of

71

No.

an object; the real value of the divisions must, therefore, for
exact measurements, be determined by means of the stage micro¬
meter for each pair of objective and eye-piece at definite tube
lengths. Approximate values, sufficiently accurate for ordinary
measurements, may, in the case of No. 28, be taken from a table
supplied with these, in the case of No. 29 they may be found
from the focal lengths of the objectives. (Fig. 30.) Inch bone
capsule .

28

The following instruments are provided with this micrometer
supplied separately in capsule: Nos. 28, 28 a, 29 and 29 a.

Micrometer Eye -piece for ordinary objectives. Huy-

ghenian eye-piece (2 or 3 as desired) with adjustable eye-lens
for exact adjustment of the micrometer scale to the eye of the
observer; with table of the micrometer values of the divisions.
(Fig. 31,) Inch micrometer No. 27 .

Fig. 31.

Micrometer Eye-piece.

28a Id. Micrometer movable laterally by means ol a

screw .

28b Id. With movable index in lieu of the micrometer. . .

The micrometer disc or the index — which is
fixed to a ring and may be procured singly at M. 1. —
are supplied in small ivory capsules together with
the eye-pieces. The tube ot the eye-piece consists
of two parts and may be screwed asunder, the line of

Maries

5 —

15.—

30.—

26.—

Qazt Oftvfcfic fyVcvkftatte, cbna.

72

No.

29

Maries

division being just above the diaphragm. Upon this
diaphragm the ring with pointer or the micrometer-
disc, as the case may be, should be placed, the latter
in such a position that the figures appear erect, and
then the two parts screwed together.

^Micrometer Eye-piece for the apochromatic Objectives.

Compensating eye-piece 6 with ‘/i micron divisions. The
divisions in this eye-piece are so computed that the value of one
interval (with a body-length of 160 mm) for each apochromatic
objective equals just as many micra q (0,001 mm), as there are
millimeters in its focal length, i. e.

Apochromatic lens: 16 mm 8 mm 4 mm 3mm 2.5 mm 2 mm 1.5mm.
Value of interval: 16 8 /it 4 3 /< 2.5 /a 2 /ti 1.5 ju.

A table of values is, therefore, superfluous for
this eye-piece, since the focus of these lenses in¬
dicates, accurately within 5 °/0, these micrometer
values . .

30.—

*ld. Micrometer scale laterally adjustable by
means of a screw .

45.-

Fig. 82.

Screw Micrometer Eye-piece.

No.

291>

73

Marhs

-52-

Id.

With movable index in lien of micrometer scale .

Screw Micrometer Eye-piece. For such exact meas¬
urements of objects which occupy a large portion
of the field and cannot, therefore, be measured with
sufficient accuracy by means of the ordinary micro¬
meter eye-piece. Ramsden eye-piece ; glass-plate with crossed
lines which are moved across the field by means of the micro¬
meter screw. — Each interval of the divided drum corresponds
to 0.01 millimeters of the objective image. Complete revolutions
of the drum are counted by means of a figured scale in the field.
With the aid of this instrument up to 8 mm may be measured
across the image formed by the objective. (Fig. 32.) . . . .

30a Id. fitted with compensating eye -piece in lieu of the
Ramsden eye-piece; for use with apochromatic lenses . . . .

31 Stage Screw Micrometer, for the exact measure¬
ment o f o b j e c t s t o o 1 a r g e to beincludedinonevisual

41.—

GO.—

80.—

Qazt Siios, (Spt-ij’cfv^ tyVczh^ldlle, 3 cna.

74

No.

field o f tli e microscope. — A sliding piece which is actuated
by a micrometer-screw carries a rotating disc with divided circle;
the divisions of the drum indicate 0,002 mm ; complete rotations
are counted by an index ; the screw measures up to 10 mm. — The
instrument is arranged to fix on the stages of the larger stands;
in the case of those fitted with rotation disc, the latter has to be
removed. (Fig. 33.) .

When ordering please to state the breadth of the stage
which it is intended for.

B. Apparatus for counting.

33

Crossed-line Micrometer, for dropping into the eye-pieces
(in particular the micrometer eye-piece s). A square of
5 mm, divided into squares of 1.0 or 0.5 mm, as required; for
counting scattered particles in the field ; in bone capsule . . .

Set of Stops of different diameters (1 to 10 mm) for dropping
into the eye-pieces — micrometer eye-piece preferably — after
P. Ehrlich .

1) For determining the numerical ratio of the various white
corpuscles in leucaemic blood.

2) For determining the relative proportions of red and white
corpuscles in cases of anaemia etc.

3) The smallest diaphragms for demonstrating objects
placed in the centre of the field and also

4) For increasing the definition of very fine structural images.

33

Crossed-line Stage Micrometer, a cross -line micrometer,
being a sq. mm divided into 400 squares, which forms the bottom
of a cell having an exact depth of 0.100 mm; the cubic contents
of the fluid resting on one square below the cover-glass are,
therefore, 1/' 400o cubic millimeters. With 2 plane cover-glasses.
In case .

Maries

120.—

5.—

5.—

15 —

75

Marks

34

Haemacytometer after THOMA. This apparatus consists
of 1) a cross-line micrometer, being a sq. mm divided into 400
squares, which forms the bottom of a cell having an exact depth
of 0.1 mm, and 2) a blood-mixing pipette (melangeur), which is
also, of necessity, very accurately calibrated. With instructions.
In case.

a) With mixing pipette for red corpuscles .

b) With mixing pipette for white corpuscles

c) The same apparatus with both pipettes
Pipettes alone.

One for red corpuscles (diluting 1 : 100)
One for white „ ( „ 1 : 10) .

30.—

32.—

44 —

12 —
14.—

35»?

b, c

The same apparatus, as Nos. U »■ b’ c, with small movable
stage, to assist the process of counting under the microscope
M. 10. — extra.

C. Measuring Apparatus for various

other purposes.

36

Brass Measure, lOO-mm, with chamfered edge

37

Measures on plate-glass, for drawings, in which the di¬
visions lie on the surface of the paper without parallaxis, with
fine, sharply engraved lines:

300 mm glass rule, divided in */i mm .

200 mm do. do. .

100 mm do. do. .

50 mm divided in */ 2 mm on a 3X1 inch slip . . . .
Any other scales to order.

1.50

0.—
5. —
1.50
1.50

Qavl Ztizs, <£>p hvfifyaUi, dtna.

76

No.

38 The latter two with double divisions, English measure
and 111m, each .

30 Fully divided Circles on pi ate -glass discs, with centre
marks, for use as transposers :

Circle 80 mm in diameter, x/i degrees .

Circle 120 mm in diameter, lj2 degrees .

40 Goniometer Eye-piece (No. 2), for estimating the angles
of microscopical objects, with divided circle and glass plate marked
with a series of parallel lines; sliding adjustment to eye-lens .

41

Cover-glass Gauge for the exact measurement of thickness
of cover-glasses, thin plates etc. — The measurement is effected by
a clip projecting from a box; the reading is given by an indicator
moving over a divided circle on the lid of the box. The divisions
show hundredths of a millimeter. Measures to upwards of 5 mm.

Fig. 34.

Cover-glass Gauge. No. 41.

42

Cover-glaSS Gauge of simpler construction ; screw with
divided disc and arrangement for regulating the pressure; rends
0.01 mm .

Maries

2.50

5.—

9.—

30.—

36.—

12.—

Drawing Apparatus.

No.

Maries

43

^Camera lucida after Abbe. The drawing surface is made
visible by double reflection, from a large plane mirror and from
the silvered surface of a small prism in the eye-point of the eye¬
piece. The microscopic image is seen directly through an aperture
in the silvering of the prism. By the concentricity thus obtained
of the pencil of rays reaching the eye from both the microscope
and the paper, the image and pencil are seen coincidently without
any straining of the eyes. With this apparatus moreover drawings
may be made on a horizontal surface without perceptible distortion.
The brightness of the paper is regulated by smoke-tinted glasses
which fit into the prism casing. The apparatus is adjusted for
the No. 2 Huyghenian and the compensating eye-pieces 4 and 6,
but can also be used with very low amplifications, and also with
the G and 10 dia. aplanatic lenses (No. 79) on the large dissect¬
ing stand I; if to be used on dissecting stand III it requires a
special fitting (which we supply for M. 8.—) .

30,-

Qazt 0'ptvj’cHe (tcitU, ckna.

78

Fig. 36.

Drawing Prism.

Drawing Prism (Camera lucida) with two prisms ; for fixing
over the eye-piece. (Fig. 36.) .

81.

Maries

Fig. 35.

Abbe Camera lucida.

The same Apparatus, with larger mirror on longer arm,
*

so arranged that the prism case together with the
mirror may be swung back round a horizontal pivot, the
underpart remaining meanwhile on the tube in its adjusted
position. (Fig. 35.) .

Arrangements for Polarisation

46

Polarisers :

I. For use with the illuminating apparatus of the large
stands. Nicol prism with flange on mounting to tit the carrier
of the condenser, se that the ordinary diaphragms and also
selenite and mica films may he placed over the polarising prism.

Fig. 87.

Polariser No. 46 I.

II. Fitting the cylinder diaphragm of the smaller stands.
Nicol prism with condensing lens .

Marks

11).—

22.50

.1 a Jena.

80

No.

47

Analysers:

I. Prazmowski prism in brass mount, for placing above the

eye-piece .

II. The same with divided circle .

48

Complete Polariscopes for the larger stands (with

Abbe condenser; stands I to V inch):

a) Polariser I and Analyser II (with divided circle) . . .

b) „ I „ „ I (without divided circle) . .

*

49

50

51

Complete Polariscopes for the smaller stands (without

condenser; stands VI and VII):

a) Polariser II and Analyser II (with divided circle) . . .

b) ,, II „ „ I (without divided circle) . .

Those possessing the goniometer eye - piece
No. 40 may use its divided circle in conjunction
with the analyser. The price of the polarising
apparatus is, in this case, therefore, that stated
for the polarising set without divided circle.

Eye-piece for observation of axial images.

For use with Polariser I and Analyser II. Huy-
ghenian eye-piece 2 with sliding eye-lens combined
with a collective system consisting of two single
lenses, which is adjustable to the upper focal plane
of the objective by a sliding tube. (Fig. 38.) . .

Fig. 38.

o • Eye-piece for

beries of 8 selenite and mica films after axja] i,nages.

Mohl .

Spectro-polariser, see No. 23.

Maries

20.—
35 —

54.-

39.—

57.50

42.50

30.—

10.—

Spectroscopic Eye-pieces.

Spectroscopic Eye-piece. Eye-piece with slit mechanism
between the lenses. The upper achromatic lens adjustable to
focus on the slit. Amici prism to place over the eye-piece. The
whole connected with the body by a clamping screw ....

"Spectroscopic Eye-piece (Micro-spectroscope) after

ABBE. Achromatic upper lens adjustable to focus on the slit as
above. Mechanism between the lenses for contracting and ex¬
panding the slit by symmetrical movement of the laminae (after
Merz) by means of the screw F ; these may be sufficiently widely
separated so as to open the whole visual field. The screw II
serves to reduce the length of the slit to such an extent, that,
the comparison prism being inserted, the image of the object
under investigation completely fills the slit. Comparison prism
with lateral frame and clips to hold the object and the mirror.
All these parts in a drum combined with the eye-piece.

Above the eye-piece, an Amici prism of great dispersion,
which may be turned aside about the pivot (K) to allow of the
adjustment of the object being controlled, the prism being retained
in its axial position by the spring catch L. A scale is projected
on the spectrum by means of a scale-tube and mirror attached
to the mount of the prism ; the divisions of the scale indicate in
decimals of a micron the wave-lengths of the section of the
spectrum superposed by them. The screw P is for adjusting the
scale relative to the spectrum.

Qazl 0pti (ofic QPcifi flat te, 3c na.

Marls

72.

82

Fig. 39. Microspectroscope after Abbe. Fig. 40.

Section through centre-line Slit mechanism

of the whole instrument. (Plane. Full size).

(7, full size.)

No.

Maries

The apparatus is inserted into the tube in place of the
ordinary eye-pieces and is clamped to the former by means of
screw M in such a position that the mirrors A and 0 serving
to illuminate the comparison prisms and the scale of wave-lengths
are simultaneously illuminated by sun-light. (Fig. 39 and 40.)
In case, including a set of lithographed scales for recording obser¬
vations .

165.—

54

*MicrO-SpectrO-photometer after ENGELMANN for quanti¬
tative micro-spectrum analysis, constructed on the principle of
Vierordt’s spectro-photometer. In place of the eye-piece the
casing A is attached to the body of the microscope by the tube
B \ it contains two conaxial, independently movable slits in juxta¬
position, which are symmetrically opened and closed by right
and left handed screws. The width of each slit is read off accu¬
rately on the drums T and T‘ to 0.01 mm and may be estimated
to the approximation of 0.001 mm. The one slit is occupied by
the image of the object under investigation, and the other is
illuminated by light from the source of comparison, which is

HI*

83

Fig. 41.

Fig. 42.

Micro-spectro-pliotometer after Engelmauu.

QaiA Sciw, 0pli fcfie fyPezfiftatU, cJena.

84

brought to it by a reflecting prism arranged above it and a
lateral tube d with collimator lens, diaphragm carrier n and
mirror S (or incandescent lamp).

In the upper opening of the box A either an eye-piece may
be inserted and, by means of a sliding sleeve, made to accurately
focus on the slit, or, instead of this (after proper adjustment of
the image of the specimen to focus on the objective slit), the
spectroscopic apparatus a' A' B C may be adapted and fixed in
the proper azimuth by a click mechanism. This apparatus consists
of the casing A‘ which on one side, the upper end of a', contains
a collimator lens l, which serves to parallel the cone of rays
proceeding from the objective before they enter a Rutherford
prism P of great dispersion. By the lens l' on the other
side, at the lower end of B, the parallel rays proceeding from
the prism are again brought to a focus ; and this real spectrum
is observed through an eye-piece L. By 2 slit mechanisms mounted
at right angles to one another and actuated by the screws t V ,
u u‘ in the focal plane of the eye-piece, the visual field can be
limited at pleasure after Vierordt’s manner.

By means of two lenses shown at C , an image of a wave¬
length scale is projected on the spectrum by reflexion from the
end-surface of the Amici prism, which is illuminated by the
mirror S‘ and put out of action by closing the shutter d‘. Ad¬
justment of this scale is made by inclining the whole scale-tube C
by means of the screw w with its counter spring v (Figs. 41
and 42) (vide Zeitschr. f. wiss. Mikroskopie V, p. 289, 1889)

Maries

480.—

Various Optical and Mechanical

Apparatus.

Stereoscopic Eye-piece.

No.

55

^Stereoscopic Eye-piece after ABBE, for stereoscopic and
indifferent binocular observation of microscopical objects with any
degree of high magnification (Carl’s Repertorium d. Experimental-

Marks

(2 <xzA (Sptij’cA.e tyVet&'flatte, 3ma.

86

No.

Marks

physik, 1881, p. 298; Journ. of the R. Micr. Soc. 1881, p. 203).
The division of the pencil of rays emerging from the objective to
produce two separate images is effected at the upper end of the
tube by partial reflexion at a thin stratum of air between two
juxtaposed glass prisms a and b. The direct rays proceed to an
eye-piece B, arranged in the axis of the tube, the reflected rays
undergo another reflexion through a prism b' in a second eye-piece
B‘ placed excentrically so as to make its axis and that of the
tube include an angle of 14°. Both eye-pieces give images of
equal magnification. The excentric eye-piece may be adjusted by
a screw D to suit the inter-ocular width of the observer. Bisection
of the pencil for producing stereoscopic effects is made by ad¬
justable semi-diaphragms above the eye-pieces; without these the
apparatus gives binocular non-stereoscopic vision. Available with
low or high power objectives (only achromatic) on any of the
large stands provided with rackwork coarse adjustment and which
permit of the body being shortened to at least 140 mm. (Fig. 43.)
In case .

150.—

In ordering this binocular apparatus for any microscope
it will be necessary to send a sharp sealing-wax impression
of the upper end of the tube.

56

Reversing Prism after NACHET (p r i s m e redresse u r),
for obtaining erect images when using the compound microscope
as a dissecting microscope. With plate mount to rest on No. 2
eye-piece .

18.—

57

^Diffraction Plate after ABBE, for demonstrating the effects
of diffraction in the formation of microscopical images (Monthly
Micr. Journ., Febr. 1877, p. 82; Dippel, Mikroskop p. 144).
— Three cover-glasses silvered at their lower surfaces, with
traced groups of parallel and crossed lines, cemented on a glass
slip; in case .

7.—

87

No.

57a

"The same, with a set of diaphragms and an arrangement
for placing and revolving the same above the objective, designed
for objective . .

58

Bulls-eye Lens, lOO mm in diameter, on stand ; in case

Idem 80 mm

Idem 60 mm .

59

Microscope Lamp. Gas lamp of special construction
mounted on brass stand with vertical adjustment and combined
with glass globe (No. 59a) of about 150 mm (6") dia., which
when filled with water or ammonio-cupric solution acts as a
condenser.

To obtain a proper illumination the gas flame should be about
15 cm (6") behind the globe, and the mirror of the microscope the
same distance in front of it with the most concentrated part of
the cone of rays impinging on it. — The lamp gives an excellent
bright and white light which almost completely supplies the place
of good daylight .

59

Glass Globe and wood-stand alone

60

Hand Spectroscope (Pocket Spectroscope) after Browning,
for observing the effect of absorption in larger objects — with
adjustable slit and Amici prism of high dispersion.

a) Without comparison prism .

b) With comparison prism .

(Bait Seico, <£)plt(che ^IViiti^taKi, chua.

Marks

12.—

50.—

36.—

27.—

30.—

5.—

30.-

40.—

88

Fig:. 44.
Sacchari meter.

No.

61

Maries

Saccharimeter, for estimating the percentage of sugar in
tiuids. With tube for liquids 200 mm long made to slide in a
brass tube, which carries a polariser and double quartz plate at
one end and at the other an analyser with divided circle. The
circle is divided to semi-degrees, and tenths can be estimated
with accuracy. Observation is made by adjusting the so-called
transition colour on both halves of the quartz plate, the tube being
directed by hand towards a white surface. Only suitable for
tiuids containing a small percentage of sugar. (Fig. 44.) With
directions . 65. —

61«

Idem with small telescope for the more accurate observation
of the double quartz plate .

75.—

62

'"Warm Chamber for keeping microscopical objects at
certain temperatures during observation. After Pfeiffer.

The heating-stages ordinarily used for this purpose leave the
observer in doubt, as to whether the temperature, to which the
object is raised, really corresponds to that indicated by the
thermometer. The present arrangement affords full security on
this point, as it permits of the object, together with the stand
and the surrounding air being brought up to and maintained at
a certain temperature.

89

s

Fig. 45.

Warm Chamber.

No.

Marks

It consists of a mahogany box enclosing the whole stand in
a nearly air-tight manner ; in the anterior wall is a glass window
to admit the necessary incident light; on both sides are closely
fitting doors to allow of the specimen being moved by the hands.
The whole stands on a thick metal plate and tripod. The former
is heated from below by a gas-burner controlled by a thermo-
regulator. The temperature inside the box is observed by a
thermometer and may be raised up to 45 0 C without detriment
to either stand or objectives. (Fig. 45.)

Qazi Scias, (9-pti^cA.e dcna.

90

No.

a) For large stands (I, Ia, plioto-micrographic stand) .

b) For medium stands (IIa, IV, V) .

With Micro-burner M. 7. — more.

Maries

70.—

60.—

63 Turn-Table on wood base for ringing specimens .... 9. —

64 ^Attachable mechanical Stage. (Fig. 46.)

This mechanical stage may be readily attached by any one
to stands I, IIa, IV, V and “Babuchin” stand.

It is in principle similar to those designed by Mr. Mayall
and Herr Reichert. Two sliding pieces mounted at right angles
to one another after the manner of a lathe slide-rest are moved
by means of two milled heads S, T (the rotation of S effecting
by rack and pinion the forward and backward motion, that of T
. the lateral movements). These sliding pieces pass along millimeter
scales 'which serve to record their position at any desired move¬
ment*). The object slide is so placed as to firmly rest against
the arm A on the left and against the projecting pin on the
right. Then the clamping arc D is turned to the left so as to
firmly hold the slide in its position and is fixed by means of the
left handed screw head E. To release the slide it is sufficient
to turn the clamping arc in the opposite direction. The object-
slide always remains in immediate contact with the stage of the
microscope-stand, which is imperative if the illuminating apparatus
is to exercise its full efficiency. The slide may have any size
between 48 and 87 mm length, 24 and 37 mm width .... 75. —

*) The amount of the rack and pinion movement is 30 mm, that of the lateral
movement 50 mm; the reading is taken with the aid of a simple index; but 0.1 mm
may be estimated with ease.

91

No.

Marks

65

Slide Ruler for searching section series; forms in many cases
an efficient substitute for a mechanical stage. To clamp to the

stages of stands I, IV and V .

5.-

66

“Test-tube Holder for microscopic examinations after von

Sehlen (Zeitschr. f. wissensch. Mikroskopie VII, p. 17, 1890) .

5. —

Qai-C iSeiso, Qiptvfcfit, tyX) iz&Jtatte , cJcna.

Apparatus for Projection and
Photo^micrography.

Large photo-mierographie Apparatus.

(Fig. 47.)

The general arrangement of this apparatus has remained the same as that

described at some length by Dr. Rod. Zeiss in our “Specialkatalog liber Mikro-

photographie” (German)*) and briefly sketched out in the last edition of our

catalogue (No. 28, pp. 76 to 79). In detail, however, the apparatus has been

subjected to reconstruction with the object of removing some of the difficulties

attending manipulation and also in order to render the apparatus still better
«

fitted for projection on a screen, both with high magnifications involving the
interposition of a microscope and with very low amplifications obtainable with
special low power projection lenses of long focus.

These modifications relate to the mechanical arrangement of the table
upon which the microscope or projection-stand, the source of light and the inter¬
vening auxiliary apparatus are mounted.

As in the original apparatus this table is isolated from the camera — which
is only required for photography but not for projection. Table and camera are
mounted on separate stands and are only connected during photographic exposure.
This arrangement affords a double advantage:

1) All adjustments on the microscope and its appendages may be made by
the observer with ease and precision while sitting directly before the microscope,
whereas the usual fixed combination of the two parts implies a very inconvenient
posture.

2) The apparatus readily lends itself to the purposes of demonstration by
projection.

*) Which to the extent of the present edition we are ready to forward to
applicants (price 51. 3).

93

By a very simple light excluding sleeve and by the camera being movable
the connection of the two parts is readily effected in such a manner as to exclude
the admission of external light.

Fig. 47. Large Photo-micrographic and Projection Apparatus.

A wood base 60X125 cm (24"X50"), supported by two cast-iron standards
is fitted at one end with an adjustable base- plate upon which the m icroscop e
is to be placed; the middle portion of the wood base is occupied by a horizontal
guide-bar of 60 cm (24") length while the other end of the base is left entirely
free in order to provide room for the various sources of illumination.

The principle feature of the design of this apparatus consists in arranging
the support of the microscope and its appendages in such a manner that they
are or may be once for all accurately centered, subsequent adjustment being-
only necessary for the source of illumination ; here adjustability is imperative for
obvious reasons.

In all cases where the appliances forming part of the apparatus are supplied
by us simultaneously, no adjustments beyond those effected by us and that of the
source of illumination will be needed. The apparatus when once properly adjusted
is not subject to decentration.

A more detailed description of the arrangement of the apparatus together
with short instructions will shortly follow in a separate pamphlet.

Gaz f Siijj, t)ptifcfvc ciitbz efe na .

94

No. ! Maries

67 Large Photo-micrographic and Projection Apparatus.

Schema to establish the price according to the various re¬
quirements:

I. Projection Table and its Appendage.

Wood base 60X125 cm (24"X50"), mounted upon heavy
cast-iron frame, fitted with guide-bar and adjustable s o 1 e -
plate for microscope stand .

The sole-plate is made to take and center any of the larger
inclinable stands. We recommend as an instrument specially
constructed for photo-micrography and projection and solely ad¬
apted for the 35-and 70-mm projection systems (to be used with¬
out eye-pieces) the

Photo-micrographic stand (No. 6, p. 36) .

Accessories :

Centering achromatic condenser with iris diaphragm, to insert
in lieu of the usual non-achromatic condenser (No. 20, p. 62) .

130.—

350.—

75.—

Or instead of this the simpler

Achromatic condenser without centering arrangement and
without iris diaphragm, to insert above iris diaphragm in dia¬
phragm-carrier (No. 20a) .

Centering collar for objectives used in lieu of a condenser
for illuminating (No. 17®) .

Small convex lens, to replace condenser when using very low
powers (35 and 70 mm) .

45 —

20 —

5,-

Focussing gear for turning the micrometer-head from the
distance (e. g. back of camera); arranged to slip on an upright
column on sole-plate, including a Hooke’s key . ! 15. —

To carry over

95

No.

Carried over

Optical Outfit of the Guide Bar.

Iris diaphragm of G7 mm greatest aperture, with spring
clips. On stand, which also serves as a support for a ground
glass disc .

Id. with micrometer adjustment in the direction of the optic
axis and fitted with clips, the whole serving as an object-stage
when it is required to project large objects by means of macro-
photographic lenses .

Stand with two light-filters .

1) For sun -light.

Plane reflecting mirror, on stand, with coarse and fine ad¬
justment about horizontal and vertical axis .

Heliostat (by R. Fuess in Berlin), adjusted for the polar al¬
titude of the place, which serves to keep the direction of the
incident rays approximately constant; with large mirror . . .

2) For electric arc, zircon or magnesia light.

Collective system of 120 mm (5") useful aperture, with shell
to screw in the light .

Heat filter (water-chamber) .

Stand for projection lenses of long focus (photographic systems)
Adapters for special or foreign lenses .

3) For lamp-light.

Biconvex lens on stand .

To carry over

Maries

30.—

45.—

24.—

45.—

270.—

150.—

47.—

24.—

2.50

30.—

(Scut Scisi, 0pt'i (du fyVezfiftcUtt, 3ena.

96

i

Marks

Carried over .

We supply the following illuminating apparatus at
their manufacturer’s prices:

a) For demonstration in lectures:

Electric arc lamp, projection lamp by Schuckert of Nurem¬
berg, with inclinable carbons ; about 3000 c. p. with 16 amp. . 250.

Other arc lamps according to order.

We are prepared to supply detailed information respecting
complete electric plants and shall be happy to suggest the
necessary machinery (motor , dynamomachine etc.) for our
clients. (Approximate total cost 3500 to 4000 M. for 3000
c. p.)

b) for lower magnifications, sufficient for objective demon¬
strations at short distances of screen and for photographic work
with high powers:

Zircon or Magnesia light with oxy-hydro-carbon burner.

j The complete apparatus consists of an

Oxy-hydro-carbon lamp, mounted on adjustable iron stand
with flexible inlet pipes .

Platinum disc to receive the incandescent body, 10 mm dia.

Incandescent body, disc of zircon, 10 mm dia .

,, „ prepared magnesia 10 mm dia. . . .

Gas generator for continuous supply of oxygen .

Gasometer, made of copper with pressure gauge for controlling
pressure of oxygen .

The chemical works of Dr. Th. Elkan, Berlin N., Tegelerstr.
15, supply compressed oxygen (100 atm.) in globes holding 1000
litres (price M. 10.).

40 —
5.—
3.—
0.40
30.—

130.—

To carry over

97

Marks

Carried over

c) Sufficient for photography (long exposures being required
for high amplifications) :

L a m p - 1 i g h t.

Argand burner with adjusted air-inlet (microscope lamp No. 59
without water globe) .

Auer’s incandescent gas-light will also be found to yield a
good illumination ; its successful application implies, however, some
experience.

II. Large Photo-micrographic Camera.

25 —

Mounted on two cast-iron standards on a level with the pro¬
jection apparatus. The camera, which is mounted upon a light
iron frame slides backwards and forwards as a whole. Greatest
length of bellows 1.5 m (o' 9") ; this length may be shortened to
any desired degree. The bellows consist of two parts. The part
nearest the microscope may be fixed in a vertical or any other
intermediate position ; front and back of this part may be moved
independently of each other by means of rack and pinion. The
dark slides, which fit both parts of the bellows, are made to take
plates 24X24 cm (9X9") and can be supplied with frames for
smaller sizes.

Price o f t h e camera, incl. ground and unground focussing-

plate, double dark-slide .

Movable dark-slide for making exposure-scales. The sensitive
plate is arranged to slide behind a slit cut in a fixed screen and
upon it a series of narrow strips of the central portion of the
object may successively be photographed with varying exposures
Achromatic focussing lens mounted in tripod .

Total

195.—

25.—

18.—

Separate double dark-slides, each . 20.—

Frames for plates for any standard or orther size, each . . 1.50

Qa.i/1 SeiiO, 0pti (Ac SKhcft (latte, 3c na.

98

No.

68 !

1 Maries

Small (horizontal) Photo-micrographic Camera after
Francotte. (Fig. 48.)

Fig. 48.

Fraucotte’s Small Photo micrographic Camera.

Bellows K GO cm (2') in length, made to slide on a firm
wooden base-board and capable of varying extension. A three
screw levelling stand JB placed upon the base-board serves to
adjust the position of the microscope (which must be of the
inclinable type) with respect to the camera. The base-board is
fitted with an extension board upon which may be placed the
source of light or any of the auxiliary apparatus interposed
between the microscope and the source of light in the case of
the large apparatus described on the preceding pages. These
appliances, if required for the Francotte Camera, are fitted
with a “round foot”.

Price of camera incl. double dark-slide 20X20 cm (8X8")>

ground and unground focussing-plate .

Separate double dark-slides, each .

Frames for any standard or other size, each .

70.—

18.—

1.50

Auxiliary apparatus the same as in the case of the large
camera.

99

Maries

*Small Vertical Photo-micrographic Camera. (Fig. 49.)

Fig. 49. Small Vertical Photo-micrograpliic Camera.

Bellows having a length of 45 cm (18"). Either camera-end
may be moved up or down along the sliding-bar S by means of
the collar-rings P and Q and may be clamped in any position.
Rod S is pivoted in the socket B and by this means the camera
may be readily placed over the microscope or swung away from
it. The apparatus may be mounted upon any firm table.

Price with double dark-slide for 12X15 cm (43/4X8") plates,
ground and unground focussing-plate .

Separate double dark-slides, each .

Auxiliary apparatus the same as in the case of the pre
ceding camera.

75.—

15.

Qtxzl Seico, 0-ptvfcfi.e eftna.

Dissecting Microscopes
and Magnifiers.

Dissecting Stands.

^Dissecting Stand I after Paul Mayer. Heavy horse¬
shoe foot; the stage consists of a large metal frame (10X10 cm
= 4X4 in.) to which are attached wooden folding handrests ;
adjustment by rack and pinion, plane and concave mirrors with
universal motions. The triple dissecting system No. 76 forms a
suitable combination for “teasing” small objects on a slip or
in a watch-glass ; it may be fixed in the ordinary lens-holder and
| a metal plate with stage opening of the usual size, which can be
closed below by a black or w bite disc, may be placed under
the object into a recess provided in the stage-frame. In the
examination of large objects, particularly living
aquatic animals, the aplanatic lenses Nos. 78 and 79 (6 and
10 dia.) will be found useful ; they fit into a separate arm which
may be inserted into the ordinary lens support and, by this
arrangement, the whole of the stage can be scanned. In this
case the metal stage is replaced by a glass plate, and the above-
mentioned white and black discs serve as convenient means of
modifying the illumination. With low powers a disc of white
drawing paper should be clamped over one of this mirrors by
means of a clamping ring supplied with the instrument for this

Marks

101

(Bait Sei^D, (Sptij’cA-c Vtfi|tdUc, cJcua

Fig. 50.

Dissecting Stand I,

102

No.

Maries

purpose. A brass plate made to fit tlie frame serves as a support
for small dissecting dishes which may be cemented to it by means
of paraffine; by means of a separate arm also dissecting lens
No. 76 may be conducted over the entire stage. The whole in
mahogany case fitted with lock and handle. (Fig. 50.)

Without lenses .

100.—

Application of the Abbe camera, vid. p. 77.

Fig. 51.

Dissecting Stand III.

^Dissecting Stand III. Heavy square metal base, large
stage, 75X60 mm (30X24"), to which are attached leather
covered hand-rests. Adjustment by rack and pinion ; large concave

103

mirror. Arranged for Nos. 76 and 78 (10 and 20 dia.). A separate
lens holder required if lens No. 79 (6 and 10 dia.) is to be used.
(Price of this holder M. 5. — .) In case fitted with lock and
handle. (Fig. 51.) Without lenses .

Fig. 52.

Dissecting Stand IY.

•Dissecting Stand IV. Constructed on our well-known
former model ; coarse adjustment by sliding the lens holder, fine
adjustment by micrometer screw. Concave mirror. (Fig. 52.)

a) In case on which it screws when in use .

b) With case and separate foot, with rests for the hands.

c) Without case, screwed to the foot .

The lenses described under the numbers from 80 to 82
are recommended as particularly suitable for this stand whilst
Nos. 76 to 79 are not suited for it.

Maries

50.—

18 —
21 —
18.—

(Sail iSeioi, ©ptifeke fyViififtaUc, Sena.

104

Fig. 53.

Dissecting Stand V.

No.

73 Dissecting Stand V. Small brass stand with stage, above

wljiclr a lens slides up and down in a holder. (Fig. 53.)

a) With blocks for supporting the hands .

b) Without, this .

Only suitable for use with lenses Nos. 81 and 82 or doublet
No. 80 (15 and 30 dia.).

Marks

10.—
9. —

105

Lens Holders.

Fig. 54. Lens Holder I.

Marks

Lens Holder I. Heavy metal foot, lens holder with hinge
joints, rack and pinion for focussing .

Fig. 55. Lens Holder II.

I

Lens Holder II. Heavy metal foot with vertical brass rod
and sliding lens holder .

The lens holders are specially constructed for use with
the BRUCKE lenses Nos. 83 and 84, but can also be employed
with other low power lenses (Nos. 79 and 81).

25.—

12. —

Scis>, 0ptvfcKc tyVit fi ftatti, ckua.

Dissecting Lenses.

No.

76

Maries

'Dissecting Combination Lens, consisting of three achro¬
matic lenses (objective) and an achromatic concave eye-piece;
magnifying 100 diameters with a working distance (9 mm) which
affords ample room for convenient manipulation with knife and

needle during observation .

By unscrewing the third and second lens of the objective
and using the latter without the eye-piece a useful series of
graduated magnifications may be obtained as shown in the follow¬
ing table:

3 lenses with eye-piece 100 diameters

1 ?? ?? r 40

3 „ without „ 30

2 „ „ 20

1 „ „ ,7 15

40.-

Fig. 56.

Aplanatic Lens after Steinlieil, with Handle.

78 Aplanatic Lenses — Steinheil’s formula — composed of
three cemented lenses, giving relatively long focal distances with
large flat field ; the higher lenses for use with the dissecting
microscopes, the weaker ones as hand lenses or with a lens
holder. Magnifying 6, 12, 20; in wood capsule, each . . . .

12. —

107

Fig. 57.

Improved Aplanatic Leus.

No.

Maries

79

Aplanatic Lenses, of similar construction, with exception¬
ally large field, the lower type suitable for use with Abbe camera
No. 43 or 44 (vid. p. 77) ; 6 and 10 diameters ; in wood capsule,

each .

15 —

Handle with ring for lenses 78 and 79 .

3 —

Tripod for same .

3.—

80

Doublets, old formula.

a) X 15 in case .

0.—

b) X 30 „ „ .

G.-

c) X 60 „ „ .

Designed for the dissecting stands IV and V ; not suitable for
free hand work owing to the high amplifications.

9.—

81

Magnifier, two lenses in brass mounting, magnifying 10,

lower lens alone 5, in capsule .

Designed for dissecting stands IV and V and also as a hand
magnifier.

0.—

82

Magnifier, same construction simplified for dissecting stand V,

in wood capsule .

4. —

83

Dissecting Lens after Brucke, with long focal distance,

magnifying 4 to 5 times .

11.—

(Bazi 0pt ifcfie QVzzfz^tattc, dzna.

108

No.

Marks

84

Dissecting Lens after Brucke, double objective with achro¬
matic lenses of 33 mm aperture and sliding eye-piece, magnifying 5
to 10 times .

30.—

.

The above two numbers are specially designed for the lens
holders Nos. I and II.

Hand Magnifiers.

87

Achromatic Magnifier, in ivory mount to fold, as above,
with two achromatic lenses; magnifying 3, 5 and 8 .... .

12.—

109

Synopsis of Magnifiers.

I

-- —

—

—

— - - -

No.

Type

Magni¬

fication

Focal

distance

Visual

field

Price

Mks

mm

mm

78

79

80

84 f

Steinheil

aplanatic lenses

Improved
aplanatic lenses

a)

Doublet <(b)

c)

Magnifier

Brucke

dissecting lenses

6

12

20

6

10

17

33

70

10

5

5—10

34

20

10

32

12

13

5

2.5

13

70

70—60

18

9

3.5

30

15

4

2

1.2

14

20

13-7

12 —
12.—
12 —

15.—
15 —

6.—
6 —

9.—

4. and 6.

11.—

30.—

Remarks. The magnification is calculated for a normal image distance
of 250 mm (10").

The focal distance is the distance between the object and the lower
surface of the lens, as adjusted by a normal-sighted observer.

The distance given above is rather smaller with short - sighted and greater
with long-sighted persons.

The same applies to the given linear diameter of the field.

These values are , therefore , only approximated and intended to give a
rough idea.

(2a tf iSevw, (Sptij’cfic tyVafiftaUi, 3i tia.

Microtomes.

We have discontinued to supply the ROUTING microtome.
Of late years the more elaborate microtomes have undergone
such manifold changes and have become so complicated, that
only workshops which devote themselves to this special branch
under the constant guidance of experts can hope to manu¬
facture them with any success. We, therefore, limit ourselves
to the simple microtomes which we have been making for a
number of years and which admittedly answer the purpose
for which they were designed.

I

Fig. 58.
Microtome.

Microtome after our former pattern. Round polished glass
I plate 80 mm in diameter, supported by two pillars on a heavy
brass foot, on which the knife is worked by hand. The specimen
j to be cut is imbedded in a brass tube and pushed up through an
opening in the plate by a screw with divided head. The divisions
on the head indicate the thickness in hundredths of a millimeter.
(Fig. 58.) With knife, in small case .

Maries

I

40 —

Ill

Hand Microtoma. Round flat brass plate 80 mm in diameter,
with a cylindrical jacket by which the instrument is held in the
hand and through which the specimen is advanced by a screw.
The thickness is indicated on a divided disc. For use with an
ordinary razor . . .

I

Fig-. 59. Francotte’s Microtome

91

^Microtome after FRANCOTTE, similar to the above ; the
knife is worked by a metal carrier (d), and the whole may be
fixed to a table by a clamping screw (a). (Fig. 59.) . . . .

92 Knives for the microtomes 89, 90 and 91. Large razors

with straight blade and folding handle .

In order to meet the wishes of our friends abroad we
shall be glad to procure for them, together with the micro¬
scopical outfits ordered:

Microtomes,

Complete sets of dissecting instruments,

Collections of microscopical specimens.

In such cases please to state the approximate prices.

Marks

18.—

30 —

5.—

0ptif’dVc fyVtzfiftaite, chna.

Slips and Covers.

No.

93

Slips of the Giessen Pattern — 28X48 mm .

94

a) white crown-glass with ground edges, per 100 . . .

b) „ „ „ „ unground edges, per 100 . .

c) best white plate-glass with ground edges, per 100 .

Slips of the English Pattern — 76X26 mm :

7(3X26 MS

a) white crown-glass with ground edges, per 100 . . .

b) „ „ „ „ unground edges, per 100 . .

c) best white plate-glass with ground edges, per 100 .

Maries

3. —
2. —

4. —

3.50

2.50

7.50

113

No.
95

90

97

Slips of extra large size — 87X37 mm

a) white crown-glass with ground edges, per 100 . .

b) „ „ „ ,, unground . edges, per 100 .

c) best white plate-glass with ground edges, per 100

Hollow Slips:

a) small pattern, 55X32 mm, of best make and finish, ground

edges, each .

b) extra large, 87X37 mm, of best make and finish, edges

ground and polished, 5 mm thick, each .

Slips with cemented glass rings, for moist chambers l
or 2 mm deep, each .

Marks

o.

3.50

9.—

0.50

1.—

0.80

98 Covers square :

size : 24 21 18 15 12 mm □

per 100 Mk.: 4.70 3.60 2.70 1.80 1.—.

@cuC Sei», <£)ptvfcA.e sK?akj(iHU, cJena.

Marks

Covers, round:

size: 24 21 18 15 12 mm diameter

per 100 Mk. : 6.90 5i50 4.20 3.00 L50.

Covers, oblong:

size : 32X24 mm , 24X21 mm
per 100 Mk. : 64X) anCl 4.50.

24X21 M —

The thickness of the above covers varies between 0.15 and
0.22 mm ; one third more must be added to the above prices for
covers of given thickness.

Complete Microscopes.

For the convenience of the buyer we have compiled the following series of
suitable and current combinations with the total price appended.

In ordering either of these sets it will be sufficient to quote the respective
number and price.

1) Microscope:

Stand Ia with mechanical stage . M. 400. _

Apochromatic Objectives :

16.O mm, 8.0 mm, 4.0 mm
0.30 n. ap. 0.65 n. ap. 0.95 n. ap.

IOO— 130.— 180.— . M. 410 —

2.5 mm (Water Immers.)

I.25 n. ap.

3°°— . . 300 —

2.0 mm, 3.0 mm (Homog. Immers.)

1.30 n. ap. 1.40 n. ap.

400.— 500— . . 900.— >f 1610, —

Compensating Eye-pieces :

2, 4, 8, 12, 18

20 — 20.— 20.— 30 — 30 — 25.— . . 145. —

6 with 1jl micron divisions (Micrometer Eye-piece No. 29) ,, 30. —

Projection Eye-pieces :

2, 4

40. — 40. — .

Goniometer Eye-piece No. 40

80. —

„ 30 —

„ 285.—

Carry forward M. 2295. —

( Sat'f 0p tijcht QVcvh^tdtti, Sena.

116

Brought forward

Apertometer No. 2 • . . .

Test-plate No. 3 .

Sliding Objective-changer No. 25 with 6 Objective-slides

Case for 6 slides .

Stage Micrometer No. 26 . .

Screw Micrometer Eye-piece No. 30a .

Stage Screw Micrometer No. 31 . . . . .

Crossed-line Micrometer No. 32 . .

Apparatus for counting blood corpuscles No. 34c . . . .

Measures No. 36 and 37, 100 and 300 mm respectively

Fully divided Circle No. 39, 120 mm dia .

Cover-glass Tester No. 41 .

Camera No. 44 .

Polariscope No. 48s (Divided Circle of the Goniometer

Eye-piece No. 40) .

Series of Selenite and Mica Films No. 51 .

Spectroscopic Eye-piece No. 53 . . .

Microscope Lamp No. 59 .

Saccharimeter No. 61 . .

Turn Table No. 63 .

M. 80.—
10.—
.« 70.—

.. 7*-

„ 10—

„ 80.—

„ 120.—

” 5'

" 44' —

„ 10.50

9-—

36—

„ 42.—

» 39—

„ 10 —

M I65.—
11 30 —
v 65.—
m 9 —

M 2295.—

„ 841.50

Apparatus for Mounting .

Dissecting Microscope :

Dissecting Stand I ....... IOO.—

Dissecting Series No. 76 . ....,, 40 —

Aplanatic Lenses No. 79, 6 and 10 . . a 15 — .. 30. —

Lens Holder I . . 25 —

with Brucke's Lenses No. 83 and 84 ...... 41. —

Microtome No. 89*) . „ 40. —

Extra Knife No. 92 . . . 5 —

Packing

170-

66.

45-—

8 50 . Mk. 3426.

2) Microscope:

Stand I'1 without mechanical Stage ...... M. 300. —

Apochromatic Objectives :

16.0 mm, 8.0 mm, 3.0 mm
0.30 n. ap. 0.65 n. ap. O.95 n. ap.

100. — 130. — 200.— . ’ . M. 430.—

2.5 mm (Water Immers.)

I.25 n. ap

300.— . . 300.—

1.5 mm (Homog. Immers.)

I.30 n. ap.

45° — . . 45° — ,, 1180. —

Carry forward M. 1 480. —

*) We are prepared to supply larger microtomes at manufacturer’s prices (vide remark p. 111).

117

Brought forward M. 1480. —

Compensating Eye-pieces :

2. 4, 8. 12, 18

20. — 20— 30.— 30. — 25. — . M. 125.—

6 with */' micron divisions (Micrometer Eye-piece No. 29)

Revolving Nose-piece No. 24c .

Stage Micrometer No. 26 .

Cover-glass Tester No. 41 . .

Camera No. 44 .

Polariscope No. 48a .

Series of Selenite and Mica Films No. 51 .

30

71

35 —

77

10. —

57

36—

71

42—

1 7

54—

10. —

M. 155—

„ 187.—

Apparatus for Mounting :

Dissecting Microscope:

Dissecting Stand I . ....

Dissecting Series No. 76 .

Aplanatic Lenses No. 79, X 6 and 10 . . .a 15.—

Packing

„ IOO.—

„ 40.—

» 30 —

170.-

4—

3) Microscope:

Stand IIa .

Attachable mechanical Stage .

Apochromatic Objectives :

16.O mm 8.0 mm 4.0 111m
0.30 n. ap. 0.65 n. ap. 0.95 n. ap.

IOO.— 130. — 180. — .

2.0 mm (Homog. Immersion) / or 3 ° mm
1.40 n. ap. V 1.40 n. ap.

Compensating Eye-pieces :

2, 4, 8, 12,

20. — 20. — 30. — 30. — .

6 with 1/1 micron divisions (Micrometer Eye-piece No. 29)
Sliding Objective-changer No. 25 with 4 Objective-slides

Case for 6 slides .

Camera No. 44 . . ...

Polariscope No. 48“ .

M. 290. —
« 75—

» 410—

„ 5°o—

„ 100.—

30—

„ 5° —

V 7—
*, 42 —

m _ 54—

M. 365 —

„ 910 —

130 —

153—

Apparatus for Mounting :

Dissecting Microscope :

Dissecting Stand III .

Dissecting Series No. 76 . .

Aplanatic Lenses No. 79, X ^ an<* 1° • . k 15.—

Extra Lens Holder for use with Diss. Stand III . .

Lens Holder I .

with Brucke’s Lens No. 83

Hand Microtome No. 90
with Knife No. 92

11

50—

11

40.-

11

30 —

>1

5 —

75

25 —

11

11.—

15

18.-

5—

Packing

17

125 —

36—

23 —
3-5°

M. 1996.-

M. 1715.50

Qaii Sciss, €)j>ii^dvc cJcita.

118

4) Microscope:

Apochromatic Objectives :

16.0 mm 8.0 mm 4.0 mm
0.30 n. ap. 0.65 n. ap. 0.95 n. ap.

100. — 130. — 180.— . M. 410.—

2.0 mm (Homog. Immers.)

I.30 n. ap . „ 4OO. —

Compensating Eye-pieces :

2, 4. 8, 12

20. — 20. — 30. — 30. — .

6 with i/l micron divisions (Micrometer Eye-piece No. 29)
Sliding Objective -changer No. 25 with 4 Objective-

slides .

Case for 6 slides . .

Stage Micrometer No. 26 .

Camera No. 44 .

This outfit costs with:
a) Stand I* with mechanical Stage

b) Stand II* .

Attachable mechanical Stage

or

c) Stand IVa .

Iris Diaphragm .

Attachable mechanical Stage

►

5) Microscope:

Apochromatic Objectives :

16.O mm 3.0 mm
0.30 n. ap. 0.95 n. ap.

100. — 200. — .

1.5 mm (Homog. Immers.)

I.30 n. ap .

Packing

Packing

Packing

y

yy

100.—

„ 30.—

yy

yy

50 —

7-~

1*

10. —

1, 42 —

M. 1049. —

M. 400 —

.. 3-5°

„ 290.—

.» 75 —

y> _ 3- ~

„ 200. —

M 15 —

.. 75--

11 3-

M. 300. —

» 45°- —

M. 1452.50

M. 1417.-

M 1342.—

Compensating Eye-pieces :

2, 4, 8, 12

20. — 20. — 30. — 30.— . „ 100. —

6 with 1/t micron divisions (Micrometer Eye-piece No. 29) „ 30. —

Revolving Nose-piece No. 24b . . 27. —

This outfit costs with :
a) Stand Ia without mechanical Stage
with

or

b) Stand IIa .

or

c) Stand IVa .

Iris Diaphragm .

Attachable mechanical Stage

Packing

Packing

Packing

M. 300 —

„ IOO—
yy 3*

m. 1310.—

„ 290.—

_ ” _ 2m_ m. 1109.—

„ 200 —

» I5-~

75-—

» 2,50 M. 1199.50

119

6) Microscope ( Outfit of the Prussian Military Hospitals):

Achromatic Dry Objectives!

AA, DD

30— 54.- .

Apochromatic Homog Immers. Objective:

2.0 mm

1.30 n. ap .

Huyghenian Eye-pieces:

2> 4 .

Compensating Eye-pieces :

4. 8

20.— 30.— .

6 with yx micron divisions (Micrometer Eye-piece No. 29)

Revolving Nose-piece No. 24b

This outfit costs with :
a) Stand la without mechanical Stage

Packing

k 7.—

or

b) Stand H» .

Packing

or

c) Stand IV» . . .

Iris Diaphragm .

Attachable mechanical Stage

Packing

7) Microscope :

Achromatic Objectives :

A) Cj E

24.— 36— 66.— .

1 12 1.30 n. ap. (Homog. Immers.) ....
Huyghenian Eye-pieces :

2> 4 .

3 with Micrometer (Micrometer Eye-piece No. 28) .

Revolving Nose-piece No. 24c
Camera No. 44 .

This outfit costs with :

a) Stand Ia without mechanical Stage

Packing

or

b) Stand II* .

Packing

or

c) Stand IV* .

Iris Diaphragm

Packing

8) Microscope:

Achromatic Objectives :
a*. A, C, F
12.— 24— 36.— 84.—

M. 84.

„ 400.

77 14 '

.. 5°--

77 3O-

.7 27.-

M. 126.—

77 300.—

7? 14- -

I5-—
77 35- —
7> 42- —

*56.

M. 605. —
„ 300 —

77 3 —

77

77

290. —
2. —

„ 200. —

7, 15 —

7. 75—

„ 2.50

M.

532.—

300.—

1 J

3 —

>>

290 _

*1

2. —

200 —

yy

15—

2.—

Carry forward M. 156. —

M. 908.—

M. 897.-

M. 897.50

M. 835.—

M. 824.-

M. 749 _

QazC (9p tifcfu Wiihjt&tti, Sena,

120

Brought forward M. 156. —

Water Immers. Objectives:

D\ J

75 — 1 44- — . « 219—

Huyghenian Eye-pieces :

2, 4 . & Mk. 7. — „ 14. —

3 with Eye-piece Micrometer (Micrometer Eye-piece No. 28) ,, 15. —

Revolving Nose-piece No. 24b . „ 27. —

Camera No. 44 . „ 42. —

This outfit costs with :

a) Stand Ia without mechanical Stage .

or

b) Stand IIa

or

c) Stand IVa

Iris Diaphragm

Packing

Packing

Packing

M. 473.—

i> 300 —

3 —

290.—
2. —

200.—

I5-~
2 — -

»>

M.

M.

M

0) Microscope ( greatly patronized by physicians, surgeons
and veterinarians) :

Achromatic Objectives :

AA, DD

30.— 54.— .

1

12 1.20 (Homog. Immers.)
Huyghenian Eye-pieces :

2. 4 .

a Mk. 7. —

Revolving Nose-piece No 24b .

This outfit, representing according to Prof. Koch of Berlin
the minimum required for bacteriological in¬
vestigations, costs with:

a) Stand Ia without mechanical Stage .

Packing

or

b) Stand IIa

Packing

or

c) Stand IVa . .

Iris Diaphragm

Packing

M.

84.

160

H-

27-

M. 285.

300

3-

290.

2-

200.

15

2.—

M.

M.

M.

10) Microscope ( for the same purposes, but a little cheaper
than outfit 9):

Achromatic Objectives :

A, D

24. — 42. — . M. 66.

12 1 .20 (Homog. Immers.) . „ 160.

Huyghenian Eye-pieces:

2, 4 . Mk. 7.— „ 14,

Revolving Nose-piece No. 24b . . „ 27.

„ 267.

776.—

765.-

690.—

588.—

577.-

502. —

121

This outfit costs with :

a) Stand I» without mechanical Stage

or

b) Stand IT* .

or

c) Stand IVa .

Iria Diaphragm .

Packing

Packing

Packing

M. 300.—

or

d) Stand IVb .

Illuminating Apparatus No. 18 with Iris Diaphragm .

Packing

or

M

M.

e) Stand Va (see remark on p. 46 regarding applicability
of immers. systems with these stands) .

Iris Diaphragm .

Packing

or

f) Stand VII (see remark on p. 46 regarding applicability
of immers. systems with these stands) .

Illuminating Apparatus No. 19 .

Small Iris Diaphragm .

. Packing

11) Microscope:

Achromatic Dry Objectives :

A, D, P

24- — 42- — 84. — . M. 150.—

Huyghenian Eye-pieces :

2) 4 . h Mk. 7. — ,, 14.

Revolving Nose-piece No. 24b . 27.

This outfit costs with:

a) Stand IVa .

Iris Diaphragm .

or

b) Stand IVb .

or

c) Stand Va .

or

d) Stand VI .

12) Microscope:

Achromatic Dry Systems :

Ay C, E

24. — 36. — 66. — .

Huyghenian Eye-pieces:

2, 4 .

Packing

Packing

Packing

Packing

yy

3—

yy

290.—

yy

2. —

yy

200. —

yy

15—

yy

2. —

yy

150—

yy

yy

40.-

2. —

yy

120 —

yy

IS—

yy

2.—

yy

60 -

yy

10. —

yy

12. —

yy

1.20

- M.

191.—

yy

200. —

yy

i5—

M

1.80

yy

Ln

O

1

yy

1 80

yy

120. —

yy

1.80

yy

65.—

yy

1. —

M

M

M.

M.

M.

M

M.

M.

M. 7.—

M 126.

14-

Revolving Nose-piece No. 24b . . 27.

This outfit costs with :

a) Stand IV» .

Iris Diaphragm .

Packing

M. 167. —

200. —

IS—

1.80

M.

Gaz( %ii», <£)-p tvfcfie tylhvh ftattt, dina.

570,-

559, —

484.—

459.—

404.—

350.20

407.80

342.80

312.80

257.-

383.80

122

or

b) Stand IV'’ . M. 150.—

Packing

99

I.80

M.

318.80

or

c) Stand V» . .

99

120. —

Packing

99

1.80

M.

288.80

or

d) Stand VII .

97

60. —

Packing

99

I. —

M.

228.-

13) Microscope:

Achromatic Dry Objectives:
a2, B, D

12. — 30. — 42. — .

Huyghenian Eye pieces:

84.-

2, 4 .

This outfit costs with :

I4— M.

98 —

a) Stand VII .

Packing

99

99

60. —

I. —

or

b) Stand IX .

or

Packing

1, 4° —

„ 1.20

c) Hand Microscope No. 16

Packing

„ 15 —

99

M.

M.

M.

14) Microscope for the detection of Trichina
after Professor Johne:

Stand IX with specially constructed Triple Objective and

2 Eye-pieces; 6 Amplifications from 30— 190 .... „ 70. —

Packing „ 1.20

159.-

139.20

113.-

71.20

Index.

page j

S, A, AA-Objectives . .

20—22

Achromatic Objectives

19—22

55 „ combined

with Compensating Eye-pieces

. 20

Accessory arrangements for testing

the fundamental properties

of

microscopical objectives

24—25

Apertometer

Adjustment, coarse, fine

. 29

Analysers and Polarisers

. 80

Apochromatic Objectives :

Introduction of the ..

. 1

Properties of the „

7—11

Durability of the „

. 10

New constructions ...

11—13

Price list .

Magnifications with the Comp

en-

sating Eye-pieces . .

16—17

Apparatus for counting blood

corpuscles after Thoma

. 75

Apparatus for photo-micro-

graph y .

92—99

Arc lamp, electrical . . . .

. 96

Arrangements for polarisation

79—80

Axial images , Eye - piece for ob-

servation of .

56, 80

B -Objective .

21—22

BB-Objective . . .

. 20

Babuchin, Stands ....

42—45

Bertrand's Eye-piece . . . .

. 56

Bull’s Eye Lenses . .

page

... 87

Browning, Hand Spectroscope after 87

Body-length for which

the ob-

jectives are adjusted .

... 4

— of the stands .

C Objective .

21—22

CC-Objective .

... 20

Camera lucida . . . .

56, 77—78

Cap bottles for immersion

oil . . 21

Cases for the stands

... 31

Cedar-wood oil .

... 21

Centering Arrangement for the illu-

minating apparatus

, . 59, 61

Circles, fully divided . .

... 76

Clamping ring ....

... 48

Compensating Eye-pieces

15—17

Condenser, achromatic .

... 62

Condenser systems .

14, 58, 61

Correction of the spherical and

chromatic aberrations . . 1, 5, 7, 8

Correction Adjustment .... 5

Covers . 14, 113 — 114

Cover-glass gauge . 7G

Crossed-line Micrometer . . . . 74

Crossed-line Stage Micrometer . 74

Cylinder diaphragms . 30, 32, 58, 61

D, DD, D -Objectives 19 — 22

Diaphragms to insert in the Eye¬
pieces after Ehrlich . 74

<2az C Scico, <9p tifcfii chua.

124

page

Diffraction Plate after Abbe 86 — 87

Distance of object . 4

Dissecting knives etc., set of . .111

„ lenses . 106

„ stands .... 100 — 104
Divided Circles . 76

Drawing apparatus . . . 56, 77 — 78

Draw Tubes with millimeter scale 29

E-Objective . 21 — 22

Engelmann , Micro - spectral Ob¬
jective . 64

Micro-spectral Photometer ... 82

Eye-pieces :

Axial-image „ . 56, 80

Bertrand’s „ . 56

Compensating „ . . . . 15 — 17

Huyghenian „ . . . 22 — 23, 56

Orthoscopic „ . 23

Projection „ . 18

Stereoscopic „ . 85

Spectroscopic „ .... 56, 81

I Setting of Eye-pieces .... 15

Numeration „ . 16

Eye-piece Micrometer . . . .56, 70

Engraving of names on stand . . 31

F-Objeetive . 21 — 22

G-Objective (Water Immersion) . 20

Glass globe with stand .... 87

Goniometer Eye-piece . . . 56, 76

H-Objective (Water Immersion) 21 — 22
Haemacytometer after Thoma . . 75

Hand Microscope . 48

Hand Spectroscope after Browning 87
Heating arrangement for warming

microscopical objects . 88

Huyghenian Eye-pieces . . 22 — 23

— with crossed lines . 56

Homogeneous Immersion :

Objectives for „ ... 6, 14, 21

Fluid for „ .... 6, 21

1-Objective (Water Immersion)

page

21-

-22

Illumination of the objects.
Illuminating apparatus:

•

30

for white light ....

30

for spectroscopically decomposed

light .

for monochromatic light

after

63

Hartnack .

63

after Abbe .

57-

-61

simplified .

61

small of 1.0 ap .

•

61

Image distance of the Projection
Eye-pieces . 18

Immersion fluid . 6

Immersion Objectives, achromatic 6, 21
„ „ apochromatic 6, 14

Iris diaphragm . 60 — 61

K-Objective (Water Immersion) . . 20

Knife for microtomes . Ill

L-Objective . 20

Leather travelling cases . . . . 31

Lenses . 106 — 109

Lens Holders . 105

Magnification :

Initial magnification of the Apo¬
chromatic Objectives . . . 9, 14

Eye-piece magnification . 16, 17, 23

Magnifiers . 106 — 109

Mahogany cases for objectives . . 20

Measure on brass . 75

„ „ plate-glass . 76

Measuring and counting apparatus 70
Measuring Eye-pieces . . . 71 — 73

Metal name plates . 31

Micro-burner . 90

Micrometer movement of the stands 29
Micrometer:

Stage Micrometer
Eye-piece „

Stage Screw Micrometer . . . 73

Screw Micrometer Eye-piece . 56, 73
Crossed-line Micrometer . . . 74

Crossed-line Stage Micrometer . 74

125

page

Micrometer Eye-piece . . . . 56, 71

Microscope Lamp . 87

Micro-spectral Objective after Engel-

MANN . 64

Micro-spectral Photometer . . 56, 82

Microtomes . 110 — 111

Monobromide of Naphthaline . . 14

Nachet, reversing prism .... 86

Objectives :

General Properties . . . 1 — 3, 4— 6

Achromatic Objectives . . 19 — 22

Apochromatic „ ... 7 — 14

Changing arrangements for „ 67: — 69

Objective magnification . . . 9, 14

Photo-micrography :

Apparatus for „ . 92 — 99

Stand for „ . 36

Polarisation arrangements . 79 — 80

Projection apparatus . . . 92 — 99

„ Eye-pieces . 18

„ Systems . . . . 11 — 12

Reversing prism after Nachet . . 86

Revolving nose-piece . 68

Rollet, Spectro-Polariser after . . 66

Saccharimeter . 88

Screw Micrometer Eye-piece 56, 73
Series of Selenite and Mica films 56, 80
Sliding Objective-changer . 68—69

Slips . 14, 112— 113

Sliding Ruler . 91

Specimens, microscopical . . . .111

Specialkatalog of photo-micrography 92

page

Spectroscopic Eye- pieces 56, 81 — 84
Spectro-polariser after Rollet . . 66

Spectroscope, Hand-after Browning 87

Standard Thread . 6

Stage Micrometer . 70

Stages :

Stages :

General remarks ....

26—28

Mechanical Stage for Stand F

. 34

Attachable, mechanical stage

. . 90

Stands:

General remarks ....

26—31

Large Stands .

32 37

Medium „ .

38—45

Small „ .

46—48

for crystallographic and petrolog

ical

researches .

50—55

Stauroscopic Plate ....

. . 56

Stops for Eye-pieces

. . 74

Table of Magnifications

of the Apochromatic Objectives
with the Compensating Eye-pieces 1 7
of the Achromatic Objectives with
the Huyghenian Eye-pieces . . 22

Test-plate after Abbe ..... 25

Test-tube holder . 91

Thickness of Cover, for which the
Objectives are corrected ... 5

— Measurement of the same by means
of the Micrometer screw ... 29

Thoma, Haemacytometer after . . 75

Trichina, Microscope for dissecting 48
Turn Table (Tournette; .... 90

Working Distance . 4

Working Eye-pieces . 16

Warm Chamber . 88

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