i

I

I

LIBRARY

OF THE

UNIVERSITY OF CALIFORNIA,

Gl FT OF

,
Class

— L\

CARL ZEISS -JENA

MICROSCOPES

AND

MICROSCOPICAL
ACCESSORIES

or T,.C
UNIVERSI1 r

EDITION

J906

IM. II. 06. 4000 c.

Besides this catalogue the following publications (in English, French or
German) may be had gratis on application:

Micro-photographic Apparatus for visible and also for ultra-violet

light,

Projection Apparatus, JBpiscope, Epidiascope,
Appliances for the investigation of Ultra-microscopical Particles,

Photographic Objectives (Planar, Unar, Tessar, Protar); Reversing
Prisms, Fluid Cells for Colour Screens, Focussing Glasses etc.,

Palmos-Cameras with Focal-Plane Shutter, Mininum-Palmos, Stereo-
Palmos, Universal-Palmos,

Zeiss Pack- Slide for flat films,
Tele- Adapter for Hand Cameras,
Stereoscopes and Verants,

Zeiss Field-Glasses and Portable Stereo-Telescopes (with enhanced
stereoscopic effect),

Prism-Telescopic Rifle Sights,

Binocular and Monocular View Telescopes for Portable Stands
and Stationary Motintings,

Stereo- Telemeters,
Stereo- Comparators,

Optical Measuring Instruments for Chemist and Physicist (Spectro-
meters, Refractometers, Spectroscopes, Longimetrical Apparatus, Compara-
tors, Interferometers, Dilatometers etc.),

Inter-pupillary-dista,nce Gauges for Oculists,
Astronomical and Astro-photographical Objectives,
Astronomical Telescope Mountings and Astronomical Accessories.

We shall be glad to supply for scientific publications electros of the
illustrations contained in this catalogue, also reductions of the same as far as
such are available.

Unauthorised reproduction of illustrations or of portions of the text of
this catalogue will be dealt with under the Laws relating to Copyright.

An asterisk * denotes that the appliances specified in the general part of
this catalogue have originated in our Works, i. e., were either introduced by us
as new specialities or, at any rate, first made by MS in the form described.

A.11 the items specified in this Catalogue are supplied singly or in any
desired combination at the prices quoted.

The price of the Stand includes tit (it of t/ie Stand proper with
'its cabinet or case but without Oculars, Objectives and Nose-piece.
Suitable outfits are compiled at the end of the Catalogue.

The price of a Microscope ivith its equipment is in all case*
obtained by adding together the prices of the individual items.

Our quotations are strictly Net Cash and do not include the
cost of packing and carriage from Jena. Payment may be made
by Cash, Cheques or short negotiable English, French or German Bills
of Exchange. Receipt of price and consignment of goods in Jena are held
to conclude a transaction.

Purchasers, who have not a regular account with us, are requested to send
cash with order.

G6ods are forwarded, value declared, at the risk and cost of the consignee.
In the absence of special instructions, goods ordered from abroad are despatched
by the most convenient routes, even' precaution being taken to ensure safe and
prompt delivery.

We request that the name and address may be plainly written
on all orders, and, to avoid misunderstanding/, that the number,
or year of publication, of this edition of our catalogue be quoted.

In telegraphic orders it is sufficient to quote the codeword. In
cases where several specimens of the same apparatus are required it is advisable
to indicate the quantity desired in words instead of in figures.

, 1906. Carl Zeiss.

Telegraphic Address: Zeisswerk Jena.

Branch Establishments for the purposes of sale and minor
repairs:

Berlin NW, Dorotheenstrasse 291! Telegr. Address: Zeisswerk Berlin.

Frankfort 0. M., Bahnhofsplatz 8, Ecke Kaiserstrasse. Telegr. Address : Zeisswerk Frankfurt Main.

Hamburg, Rathausmarkt 8. Telegr. Address: Zeisswerk Hamburg.

St. Petersburg, Kasanskaja-Ulitza 2. Telegr. Address: Mikro Petersburg.

Vienna 1X3, Ferstelgasse 1, Ecke Maximilianplatz. Telegr. Address: Zeisswerk Wien.

London W, 29 Margaret Street, Regent Street. Telegr. Address: Diactinic London.

Telephone: 4007 Central.

158562

Contents.

Page

Objectives and Oculars 6—26

Apoehromatic Objectives . 12—16

Compensating Oculars 16 — 19

Achromatic Objectives 20—22

Paired Objectives for Binocular Microscopes 23

HUYGENIAN Oculars 23, 24

Stands 27-69

Diaphragms and Illuminating Appliances 27 — 35

Mechanical Stages 36—40

Focussing Appliances 40 — 42

Appliances for changing the Objectives on the Stand .... 43— 4f>

Various Forms of Stands 46 — 69

Accessory Apparatus 70—93

Drawing Apparatus 70 — 74

Appliances for measuring and counting microscopical objects 75 — 81

Apertometer, Test-plate, Diffraction Apparatus 81—*;;

Appliances for microscopic examination in polarised light . 83 — 85

Oculars designed for special purposes 86 — 89

Prism Rotator, Capillary Rotator 89. 90

Appliances for artificial illumination . 90, 91

Heating Appliances , 92, 9; 5

Various other Accessories '.>.">

Bell glasses, object slides, cover-glasses 94, 95

Complete Microscope Outfits • .' . 96— no

Index 111—113

Preface.

The present 33rd Edition of our Catalogue relating to Microscopes and
Microscopical Accessories exhibits some modifications as compared with the 32.nd
Edition, which appeared in 1902, occasioned, mainly, by the introduction of several
new forms of Stands. The construction of Stands III and IV — regarding whose
arrangements we have already given full particulars in special prospectuses -
has resulted in conferring certain advantages, rendered possible by limiting the
number of the types, and by greater simplification in the mechanical equipment.
Further, we have manufactured quite a simple Stand for laboratory use, more in
accordance with present requirements of microscopical technic than our earlier
small Stands. A detailed prospectus relating to this new Stand V has already
been published.

Ill the majority of the achromatic objectives, owing to progress contin-
ually being made in division of labour with the manufacture of these systems,
we are enabled thereby to effect important reductions in price. For details
we would refer to the accompanying circular.

The list of the Magnifiers, the Dissecting Stands and Lens-Holders has
been omitted in the present edition, since a special price list containing them will
appear shortly.

The general price list appended to the last edition is in the present omit-
ted, the entry of the prices against each item being considered as sufficient.

New apparatus or changes in construction appearing for the first time in
this Catalogue are as follows:

Stand III, pp. 48, 49; Stand III M, pp. 50, 51; Stand IV, pp. 52, 53; Stand V,
pp. 45, 55 ; Corneal Microscope with GrULLSTRAND's Appliance for lateral illumin-
ation, p. 65 ; Stand XI (monocular image-erecting prism Microscope), pp. 66, 67 ;
Micro-spectro-photometer with grating, p. 88.

The two important new constructions in the sphere of microscopy, Appliances
for the investigation of Ultra-microscopical Particles by SlEDENTOPF and ZsiGMONDY
and the Micro-photographical Appliances for Ultra-violet Light by KCtHLER are
not included in the present Catalogue. Regarding this apparatus we must refer
to the detailed descriptions and price lists published by us during the course of
the past year.

Objectives and Oculars.

The Glass Works] of SCHOTT & GENOSSEN, which make a speciality of
glasses for optical and other scientific purposes as the outcome of exhaustive ex-
periments, with our co-operation, extended over several years and carried out by
SCHOTT and ABBE, succeeded in 1884 in producing a series of |new glasses
possessing certain refractive |and (dispersive properties which [render them more
valuable for the construction of microscope lenses than the crown and flint glasses
superseded by them.

The use of these | glasses, combined with the application of entirely new
formulae, has enabled us, since 1886, to produce microscope objectives
with markedly superior correction of both chromatic and sphejri-
cal aberration and, consequently, effecting a much [greater con cent r|a-
tion of light in the image than had previously been attainable. We introduced
simultaneously oculars specially adapted for use with these objectives which, beside
facilitating certain other advantages of minor importance, iproduce alm|ost per-
fect achromat-ism an|d yield a sharp image over the w|h|ole area
of the visual field.

By a special catalogue published in August 1886 these new combinations
were first made known under the designations of "A|pochroma|ti;c Objectives",
"Compensating Oculars" and "Projection Oculars" respectively; and they
have since been most extensively adopted, have met with general approbation,
and have given most ample proofj of the exceptional value of their utility in the
field of scientific research.

Side by side with the new objectives and oculars we ^continue to supply
our older achromatic objectives with their ' accompanying ordinary oculars.
For, although in the more difficult branches of microscopical research the apo-

chromatic objectives are to an increasing extent supplanting the older objectives,
yet there are a great many problems in microscopy that do not demand the
highest attainable degree of optical perfection, and in the majority of such cases
the older "achromatic" microscope will render as good and sufficient service as
ever, provided the instrument be good of its kind, i. e., skilfully and carefully
made. The objectives and oculars of the older type have certainly this advant-
age that, thanks to their much simpler construction, really good lenses of this
class can be supplied at prices considerably lower than those of the lenses of the
new series, which are much more complicated and involve in their production
an extraordinary degree of manual skill.

We should not omit to mention that all advantages derived
from the introduction of new glasses and of the fluorites, and the
adoption of improved formulae have been applied equally to the
objectives of the older type. The improvements thus effected are of con-
siderable importance, especially in the higher powers of the dry and immersion
series, which may therefore, after the example of other makers of similar con-
structions, appropriately be termed "Semi-apochromatic objectives",
or to part, also "Fluorite Systems".

To the two types of objectives just mentioned there has been added recently
yet a third, computed by VON RoHR: the type of the Monochromats. The
special features of this system are : a very perfect union of rays (spherical correction)
for light rays of a definite wave-length chosen at will, the lack of a correction of
chromatic aberration and the composition of the system from uncemented single
lenses, which are all formed out of the same material. Since there is no chromatic
correction at all, this system can only be employed in illumination with strictly
monochromatic light.

Such objectives are manufactured for the present only for the Micro-photo-
graphic Appliances for Ultra-violet Light, spoken of in the preface, since the mono-
chromatic light employed makes objectives of this correction appear suitable.
They are corrected for a wave-length 275 (iji, all lenses consisting of molten
quartz. We also supply a series of oculars, specially for use with these Mono-
chromats for ultra-violet light whose lenses are made from quartz crystals.

Since 1808 all our manufacturing processes follow the system introduced
into our works by Professor ABBE, a system which is based upon complete
theoretical computation of all the constructive data previous to
actual manufacture. By this method it has become possible, through judicious division
of labour in the various stages of manufacture under competent scientific super-
vision, to employ a large number of operatives in the production of lenses of
the greatest possible perfection.

The necessity of empirical tests has been entirely obviated by precise mathe-
matical computation of every detail of construction combined with exact technical
methods and systematic control of each phase of manufacture. This ensures an

= 8 =

extraordinary degree of uniformity in the highest as well as in the lowest
powers of our lenses, whilst excluding the bare possibility of inferior
productions. All objectives are uniformly free from spherical aberrations up
to the marginal zone (assuming correct thickness of the cover-glass with the
higher powers) and, as far as possible, from chromatic aberrations also. Special
consideration is also given to the compensation of the aberrations in the extra-
axial part of the field and to the flatness of the image.

Free 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 high power objectives possess therefore unusually large work-
ing distances in comparison to their focal length and aperture (see Tables on
pp. 15, 22 and 26).

Tube-length. The objectives specified in this catalogue, so long as
they are supplied in the ordinary mount, are all adjusted for a
tube-length of 160 mm (about 6y2 in.), reckoned from the shoulder
of the objective screw to the upper end of the draw -tube on which
the ocular rests. In Fig. 1, this length is indicated by T.

The tube-length may be read off on the larger stands of our make by the divisions
on the draw-tube. The interposition of any apparatus, such as a revolving nose-piece, a
sliding objective-changer, &c., between the tube and the objective necessitates the shorten-
ing of the tube by the length of such intermediate piece so as to make the whole distance
between objective shoulder and ocular equal to 16O mm (or about 61/, inches).

The position of the ocular is usually somewhat higher in the cane of var -
ous oculars of special construction, such as micrometer, screw micrometer, sjiec-
troscoiiic oculars, <£c. When using such oculars this must therefore be ttttoived
for, objective-changers, &c,, being, if necessary, omitted in order to maintain the
correct tube-length.

The lower-power achromatic objectives as far as C may also
without appreciable loss, be used on English stands with 10-inch
tubes.

All the other objectives, particulary those of the apochro-
matic series, perform more or less imperfectly on stands of the
English type, unless specially adjusted.

If the objectives are to be used with tubes differing from the
usual length, this fact should be expressly noted in the orders.

Thickness of cover-glass. All objectives in fixed mounts are, unless other-
wise ordered, corrected for a medium thickness of cover-glass, between 0.15 and
0.20 mm.

In the higher powers (from the apochromatic objective 8 mm and the
achromatic D upwards), with the exception of the homogeneous immersion ob-

r i -i

'T

1

i

1

j. . ...

0*

j

_<

1

i

r

1

i

j

*r*- _^~-Y.

i

i

1

^-Ji

A Fig. 1. B

A: Diagram of the path of the rays for the representation of an object point lying in the front focal

plane of the whole microscope.
B: Section through Stand III, together with the diagram of the path of the rays for the limitation of

the field of view.

/?,': hinder focal plane of the Objective AA; F, : front focal plane of the HUYGENIAN Ocular 2; F'\ hinder
focal plane of the whole Microscope ; T: effective Tube-length ; A : optical Tube-length.

V, Full Size.

Qavt

IO

jectives, that thickness of the cover-glass which gives the most perfect correction
is indicated on the side of the mount by small figures representing milli-
metres.

With those objectives, which we supply in fixed mounts only, it is, as a
rule, sufficient for ordinary work to use cover-glasses of an estimated thickness, but
for very exacting tasks we recommend the use of a cover-glass gauge (see p. 79).

A simple method of fairly accurately determining the thickness of cover-
glass requisite when using one of our large or medium stands is explained on
p. 42.

Jf it be desired that an objective should be adjusted for a
cover-glass differing front the usual thickness, or for use without
cover-glass, this requirement should be specified in the order.

Objectives with correction adjustment. Fig. 2. The divisions and numbers
on the correction collar (bb) , read off by a fixed index , indicate (in h u n -
dredths of a millimetre) that thickness of cover-glass which gives
the best correction corresponding to the position
of the collar.

The correction for cover-glass
thickness must always be carefully adjusted
- particularly in the case of the apo-
chromatic objectives 6 mm, 4 mm, 3 mm
(dry) and 2.5 mm (water immersion)
otherwise the efficiency of the lenses will be
greatly impaired.

The homogeneous immersion objectives

are supplied in fixed mounts] only, since
their efficiency, within rather wide
limits, is independent of the thickness
of the cover-gla|ss, and also because any
alteration in the lens distances would interfere
with the perfection of their correction. Consid-
erable variations in the thickness of the cover-
glasses are best compensated for

by slightly lengthening the body-tube in exceedingly thin cover-glasses,
„ „ shortening „ „ „ „ excessively thick ., „

The immersion fluid which we recommend for homogeneous objectives is
slightly thickened Cedar-wood Oil (from Juniperus virginiana) as used by
us from the first. We. expressly desire to caution against the use
of immersion fluids derived from other sources, with our objec-
tives, as the use of fluids of irregular refractive and dispersive
power may entail considerable impairment of the optical perform-
ances of the objectives.

Fig. 2.

Objective fitted with
correction-collar.

The correction-iing bb serves to adjust

the distance between the two upper

double lenses and the two lower lenses

attached to the mount aa.

(Full Size.)

1 1

Each time after use the objectives should be made scrupulously clean. The oil adhering should
be soaked up with linen or blotting paper, and then the front lens together with its mount should be
most carefully wiped dry with a piece of very soft linen moistened by a drop of benzine or xylol.

~

a b

fig. 3. Cap-bottle for Immersion oil No. 2005 and 2010.' (V2 Full Size.)

The two little bottles shown in Figs. 3a,. and 3b afford comfort and convenience in
using the immersion oil. The cap and r o'd of the bottle, No. 2005, are made of glass,
those of the No. 2010, which we originally made on specifications supplied by Dr. L. MACH
(see "Zeitschr. f. Mikrosk.", Vol. XIV, 1897, pp. 348—350), consist of metal.

With each homogeneous immersion objective of our own make
we supply gratis one of MACH's bottles with a separate flash con-
taining about 15 f/r. of Cedar-wood Oil.

For prices, ordered independently, see below.

The expression "Numerical Aperture", or "Aperture" simply, was intro-
duced in 1873 by Professor ABBE on the basis of his own theoretical investi-
gations. The value of the numerical aperture is determined by the equation :

num. Ap. = n. sin n,

n being equal to the refractive index of the medium situated between the cover-
glass and the front lens of the objective, u representing half the angle of aperture.

The numerical aperture of a lens determines all its essential qualities: the
brightness of the image increases with a given magnification, other things being
equal, in proportion to the square of the aperture]; the resolYing and de-
fining powers are directly profportional to it'; the power of differentiating
depth (the focal depth) is, for the same object medium, proportional to the co-
tangent of half the angle of aperture. (For references, see ABBE, Gesammelte

No.

Marks

Code-word

:><M):>

Bottle for Immersion oil with glass cap and rod . . .

L—

Pabellon

1010

,. „ „ MACK'S pattern

1.50

Pabulo

2015

Cedar-wood Oil 15 grms in ordinary bottle

—.75

Paeernica

&azt

= 12 =

Abhandlungen I, Jena 1904, pp. 267, 354, 365, 360, and CZAPSKI, Theorie der
optischen Instrumente, 2nd Edition, Leipzig 1904, pp. 245, 254.)

The mounts of all objectives for monocular observation are provided with
the English standard screw of about 20 mm (3/4 in.) external diameter.

The name of our firm is engraved on the mounts of all our objectives; on the
apochromatic objectives are further engraved the aperture, focal length and tube-
length for which they are adjusted, and on the achromatic lenses their distinguishing
letters.

When ordering objectives and oculars which are intended for
use with stands not made by us, it is advisable to send us the
tube in question for adaptation.

*Apoehromatie Objectives.

We cannot here do more than briefly describe the essential features of the
apochromatic objectives and must refer those who wish to make a more com-
plete study of the scientific aims and principles which govern the construction
of these lenses, to the paper of Professor ABBE, entitled "Uber Verbesse-
rungen des Mikroskops mit Hilfe neuer Arten optischen Glases"
(Sitzungsberichte der Med.-naturwissensch. Gesellschaft zu Jena, 1886, Vol. XX,
pp. 107 — 125, ABBE, "Gesammelte Abhandlungen" I, pp. 450 — 472), and to Dr.
CZAPSKI'S work on the "Theorie der optischen Instrumente", Breslau
1893, 2nd Edition, Leipzig 1904.

The peculiar characteristic which, from the optical point of view, distinguishes
the objectives of this series from all lens systems previously applied to micro-
scopes lies in the simultaneous realisation of two conditions of concentration of
rays, which conditions had hitherto not been fulfilled by any other optical system,
viz: 1) the union of three different colours of the spectrum in one point of the
axis, that is to say, the elimination of the secondary spectrum left uncorrected
in the older achromatic lenses, and 2) the correction of the spherical aberration
for two different colours, in contradistinction to the usual correction for one colour,
that in the brightest region of the spectrum, only.

With all optical systems constructed up to 1886 the greatest sharpness of the image
was limited to one particular colour of the light transmitted, while the other rays give more
or less confused images, appearing partly as colour fringes surrounding the sharpest image
and partly as a general haze spread over the whole field. But with the apochro-
matic lenses the images are for all colours of the spectrum nearly

equally sharp. The quality of the image will therefore be always uniformly perfect
whether white or monochromatic light be employed for illumination.

Again, in the older series 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 uniformly perfect
colour correction is obtained for a 1 1 zones alike. Consequently, in using ABBE'S
test plate for instance, scarcely any more colour is perceived with extreme oblique il-
lumination than with semi-lateral or with central light.

Finally, with the ordinary achromatic objectives, even within the zone of their most
complete colour correction, only two colours at a time can be united in one point and
only for this pair of colours can the images fall on the same spot, considerable focal
difference remaining for all others. But, as already mentioned, three colours are
brought to a focus in the apochromatic objectives, whereby the focal differences of the
various sections of the spectrum are reduced to fractions varying from 1/1 to l/lo of their
original magnitude, i. e., are practically eliminated, and this, we will repeat, is
done in equal degree for all zones of the objective. The images due to different colours,
each one individually corrected, are thus rendered perfectly coincident and collectively
form the final image 1).

The practical advantages of these new objectives are obvious. Their
considerably increased power of concentrating the light with ordinary visual observ-
ation or with any other mode of application - - and this under all possible
conditions of illumination, central or oblique, white or monochromatic -- estab-
lishes their acknowledged superiority over all earlier constructions , both with
respect to optical power and diversity of applicability.

The natural colours of objects, even delicate differences of tint, are
faithfully reproduced by these objectives. The images are nearly as sharp
close to the margin of the field as they are in the centre.

It is true that, owing to their large aperture and comparatively great working distance,
even in these objectives a slight curvature of the image cannot be entirely avoided.
Therefore the marginal and central portions of the field do not appear sharply
in focus simultaneously, but have to be focussed in succession by means of the micrometer
screw.

As a result of their great light-gathering power these objectives admit of
the use of oculars of very high power, while still retaining satisfactory
precision and brightness of the image and thus giving high magnifying powers

') Achromatisa t ion of a higher order in our sense of the term is both theoretically and
practically quite another thing than a mere improvement, in degree, of ordinary achromatism, such as
would result from a diminution of the secondary spectrum while yet only two colours are united; or
than achromatisation embodying the .principles here indicated but limited to one particular zone of the
objective, as would, for instance, be the case if suitable glasses were introduced in constructions of
ordinary type. -- Professor ABBE has introduced the word "apochromatic" as a definite technical
term for this particular kind of achromatism, so long familiar to scientists as a theoretical idea but only
recently realised practically. In order to avoid ambiguity it is desirable that this expression should
retain its original meaning as clearly defined by its author, and any attempt to utilise it for pur-
poses of trade advertisement of any other casual improvement in colour correction should be dis-
countenanced.

Qazl £ci«, Stnet.

with relatively great focal lengths and yielding, with the one objective, an exten-
sive series of magnifications.

The list of apochromatic objectives on page 15 specifies in addition to par-
ticulars of the numerical aperture and foci also the corresponding initial magnifi-
cation, i. e., the magnification which the objective alone would give at the distance
of distinct vision if used as a single lens. This is simply 25U (distance of distinct
vision in millimetres) divided by the focal length of the objective (also given in
millimetres). For instance, the initial magnification of a 3 mm objective is:

250

The numerical apertures indicated in the table are the guar-
anteed minimum values.

Durability of the new Glasses.

In reply to numerous enquiries and, in some cases, publicly expressed
doubts we would here state that the kinds of glass used by us since 1 *;>,"> in
the construction of apochromatic lenses, and in a limited degree for the higher
powers of achromatic objectives also, have now been so amply tested as to offer
an absolute guarantee for their permanency.

In all cases where one of the lenses of an objective supplied by us
should exhibit spontaneous changes, we shall continue, in the future (as
we have done in the past), to repair such objectives at our own cost,
substituting a new lens made of glass which has been thoroughly tested
and proved to be permanent.

To this promise we attach, however, the condition that the objective in
question be sent to us without previous meddling by others - - such as dis-
mounting with a view to cleaning - - since any interference, by inexperienced
hands, tends in many cases to convert a slight irregularity, easily rectified by
us, into a serious, or even irreparable, defect.

We should also point out that owing to the hyper-hemispherical form of
the front lens, which is held in position by a very narrow ridge at the extreme
edge of the setting, the apochromatic homogeneous immersion objec-
tives of 2 mm and 3 mm focus and 1.40 num. A p. demand very careful
treatment. Even a slight jar by contact with the object may loosen this lens in
its mount.

List of the Apochromatic Objectives.

Description

Initial
Magni-
fication

Combined with Compens.
Ocular 4- , Tube-length
160 mm (about 61/, in.)

Prices
Marks

Codeword

Equivalent
Focus
mm

Numerical
Aperture

Free

Working
Distance

mm

Diameter of
visible area
of object

mm

Dry

Series

16

0.30

15.5

5

2

80.—

Pacato

8

0.65

31

1.0

1

100.™

Pacetor

4

0.95

63

0.2

0.45

140.-

Pacer

3

0.95

83

0.15

0.35

160.-

Pacienda

\Vater-
\ Immersion

2.5

1.25

100

0.18

0.25

250.-

Paciflcar

Homo-
geneous
Immersion

3

1.30

83

0.20

0.35

300.-

Pactar

3

1.40

83

0.16

0.35

400.—

Padilla

2

1.30

125

0.16

0.25

300.-

Pndrastro

2

1.40

125

0.12

0.25

400.-

Padre

1.5

1.30

167

0.09

0.20

350.-

Padrino

Beside the objectives enumerated in this list the following apochromatic
objectives are made to order and adjusted exclusively for the 10-inch tube:

12 mm, 0.65 num. Ap Price: Mk. 140. — . Code-word: Paflon.

6 mm, 0.95 num. Ap , „ 180. — . „ Pagrauismo.

The three 6 mm, 4 mm, 3 mm, objectives of the dry series and the 2.5 mm

water immersion objective are supplied with correction-collars.

16 —

Regarding the Apochromat 2 mm, num. Ap. 1.30, with fixed stop for dark-ground
illumination for Investigation of Ultra-microscopical Particles, see Prospectuses M 163
and M 164.

As to the kind of immersion fluid to be used with homogeneous
immersion objectives see pp. 10 and 11.

By "Free working distance" as specified in the foregoing table is to be under-
stood the distance between the upper surface of a cover-glass 0.17 mm thick and the
lower surface of the lens mount, the lens being sharply focussed for an object situated
immediately below the cover-glass. As this quantity depends upon the metil mount of
the front lens, it is necessarily subject to unavoidable slight variations, and the values
given in the table are, therefore, only approximate.

The diameter of the visible area of the object is governed by the size of the
diaphragm of the ocular. The table specifies in millimetres the visible circular area of
the object in the case of each combination of component objectives and oculars. These
values, too, are slightly fluctuating, as minor variations in the diameter of the diaphragm
are also inevitable.

-- dTi—

w

Compensating Oculars.

All objectives of considerable aperture, from their peculiar construction
(hemispherical front lens), exhibit certain colour defects in the extra-
axial portion of the visual field (chromatic difference cf magni-
fication, See DlPPEL, "Das Mikroskop", 2nd Edition, Brunswick 1882, pp. 225—227 :
CZAPSKI, "Theorie der optischen Instrumente", 2ml Edition, Leipzig lldU, pp. 182,
368). The differently coloured elementary images which combine to form
the final image are of different magnitudes, the blue being larger than the red.
Whether an image be projected by such an objective without oculars, or whether
it be examined with one of the ordinary oculars, colour fringes will be observed,
increasing towards the margin of the field.

This peculiarity is shared by the apochromatic objectives also, and to their
lower powers it has even been intentionally imparted to an approximately similar
degree, a means being thereby obtained of almost entirely eliminating this
error with the aid of suitable oculars. For this purpose the latter are
made to possess an equivalent error of the opposite sign, that is, the
image formed be the red rays is larger than that corresponding to tho blue rays.
Such oculars serve thus to compensate the errors of the objectives and the
images then appear uniformly free from colour up to the very edge of
the diaphragm prescribing the limits of the visual field, whilst this edge of the
diaphragm itself shows a reddish or yellowish border.

===== 17 —

The mounts of the oculars are adjusted so that the lower focal points of
all the numbers lie in the same plane when they are inserted into the body-tube
(Fig. 4).

Ocular N°. 2

12

18

Fig. 4.
Compensating1 Oculars. ('/, Full Size.)

A A. Plane of the upper edge of the tube.

B B. Lower focal plane of the oculars.

A change of oculars necessitates therefore scarcely any alteration of focus,
the distance between the upper focal point of the objective and the lower focal
point of the ocular remaining constant. This distance, which is the determining
element of the total magnifying power, is designated "the optical tube-
length", and is designated by A in Fig. 1, p. 9, (see above-quoted work by
DIPPEL, p. 188).

In continental microscopes with apochromatic objectives and compensating
•oculars this optical tube-length is 180 mm (about 7 Vie in.), irrespective of
small differences between various objectives, the tube-length proper (see p. 8)
being in all cases maintained at 160 mm (about 6Y2 in.).

The classification of these oculars is carried out on the plan proposed
by ABBE. Accordingly, the numbers, which denote how many times an ocular
- when used with the standard tube-length - - increases the initial magnifying
power of an objective, afford a correct measure of the ocular magnifications
and, at the same time, furnish the figures for a rational series of distinguishing
numbers. In this way the series of our compensating oculars has been arranged
"by the ocular magnifications 2. 4, 6, 8, 12, 18, which supply, at the same time,
the distinguishing numbers.

The magnification at an image distance of 250 mm (10 in.) obtained by the com-
bination of a compensating ocular with any apochromatic objective may thus be quickly
found by multiplying its number by the numerical value of the initial magnification of
the objective. For instance, an objective of 3 mm focus combined with ocular 12 gives
a magnification of 12 X 83-3 = 1000 diameters.

Swiss, Sena.

j Q __^__

The exceptionally low power ocular 2, known as the Searcher Ocular,
serves to extend the effectiveness of the various magnifications required to be
successively used with any one objective as far as possible downwards through
the lower strata of a specimen, also to facilitate preliminary examination
and the process of searching for particular points of the object when high-
power objectives are being used.

The Working Oculars vary in magnifying power from 4 upwards, and even
their highest powers can be used with the greatest comfort. In all of them the
eye-point (the exit pupil) lies sufficiently high above the upper lens surface,
and the diameter of the lenses is sufficiently large, to completely obviate the in-
conveniences formerly attending the use of oculars of short focus.

We have modified one of the series of compensating ocu-
lars - • the X -I ~ ' fitting it with a collective lens of large
diameter. Under this modification it is designated Compensa-
ting Ocular 4*. As compared with the ordinary Compensa-
ting Ocular 4, its field is considerably enlarged. To
use this ocular with Stand |, the ocular-tube is unscrewed out
of the draw-tube -- with Stands III and IV the draw-tube is un-
screwed at the shoulder — and the Compensating Ocular 4* screwed
in instead. It is fitted with a revolving collar and can be fixed
rigidly in any desired position by means of a clamping screw K.
An iris-diaphragm, by means of which the area of the
field may be varied at will - - frequently a great convenience
in demonstrations -- takes the place of the ordinary fixed dia-
phragm. The eye-lens is mounted in a sliding sleeve, after the
manner of our micrometer oculars thereby adapting it for use
with a scale, &c., when desired.

Fiir. 5.

Ompensatiiifr Ocular 4*
with iris-diaphragm.

('/., Full Size.)

The enlargement of the area of the visual field is, however, of real practical value
only in the case of the lower-power objectives of 16 mm and 8 mm, because the sharp field
of the higher powers is not sufficiently large to satisfactorily fill the field of this ocular.

Should this special ocular be employed on a Stand III or \\l, possessing neither Nose-piece
or Sliding Objective- Changer, an intennediate adapting ring of definite length must be sc reived
into the main tube.

Regarding the use of this ocular with a special form of ABBE'S drawing apparatus
see p. 73.

n_

JI!

Compensating Oculars.

Searcher
ocular

Working oculars

Distinctive No.:

2

4

4*

6

8

12

18

Equivalent focal
length in mm :

90

45

46

80

22.5

15

10

Price: Marks:

20.-

20.-

40.-

20.-

30.-

30.-

25.—

Codeword :

I'MIMIU Pngote

Paurnro

Pajii

Pajada

Pajarel

Pajaro

In subsequent orders for ocular 4* the factory number of the stand with
which it is to be used should be stated.

When ordering oculars for stands of other makers it is necessary to send
us an exact impression in sealing wax of the tube edge or, better still, to send
the tube in question to our works.

Compensating oculars for the English tube. Beside those enum-
erated above the following compensating oculars are made to order for the
10-inch tube.

2e: Equivalent focal length: 135mm, Price: Mks. 25. — . Code-word: Pajarete.
-I": „ „ 67 „ „ „ 25.—. „ Pajarico.

Se: „ „ 34 „ „ „ 35.—. „ Pajarillo.

The compensating oculars for the continental tube may also be used on
the 10-inch tube, but in order to obtain correct ocular magnification for a tube-
length of 250 mm (about 10 in.) it is necessary to multiply the figures engraved
on the oculars by 1.5.

Table of Magnifications of the Apochromatic Objectives
with the Compensating Oculars.

Calculated for 160 mm (about 61/., in.) tube-length and an image distance

of 250 mm (about 1O in.).

Focus
of the objective

Searcher
ocular

Working oculars

mm

2

4&4*

6

8

12

18

16.0

31

62

!)4

125

187

281

8.0

62

12o

1ST

250

875

562

4.0 125

250

875

500

750

1125

3.0 lf,7

888

500

667

1000

1500

2.5 200

400

600

800

1200

1800

2.0 250

500

75(1

1000

1500

2250

1.5 333

667

1000

1884

2000

8000

In employing nose-piece or sliding objective-changer, the length of the nose-piece amounting to
15 mm, that of the sliding objective-changer to 22 mm. must be taken into account (see p. 8).

Qazt Sxbs, Stana.

20

Aehromatie Objectives.

Aided by the considerably extended list of materials produced by the local
Glass Works we have reconstructed most of the older types of our achromatic
objectives, the higher powers of the dry system have, moreover, received single
lenses of fluorite, so as to obviate in these objectives also, more completely than
had formerly been possible, imperfections due to spherical and chro-
matic aberration. With those systems of the dry series which have a numerical
aperture exceeding 0.65 this improvement, apart from greater sharpness and
clearness of the image, is also manifested by increased sensibility to
differences in the thickness of the cover-glass and the length of
tube. Consequently, in the use of these objectives now even closer attention must
be given to these two points than formerly.

6. Objectives at, si2, 113,

attached to the tube.

(V, Full Size.)

Fig. 7. Objective a*.

By rotation of the ring RR the

upper pair of lenses (i2) may be

elevated into the position L,' ,

indicated by dotted lines.

(Full Size.)

Our lowest power objectives, viz: a0. at, 82 and 83, are simple achromatic
lenses, so mounted, that, notwithstanding their great focal length, the body of
the microscope remains at its ordinary elevation during observation. For this
purpose lenses a» and at have their threads so situated that, when screwed into the
tube, the lens is inside the body (see at, Fig. 6), and they cannot therefore
be used with a revolving nose-piece or other objective-changer.
Though the former is primarily intended for use with our binocular microscopes,-

= 21 =

we now also supply it in a mount resembling that shown in Fig. 6 (ai) thereby
adapting it to other stands. Should the systems 3o and ai be employed on the
Mineralogical Stand III M or Stand XI -- which must be expressly so stated
in the order - - it is given a similar mount as the system 83; they can then
also be employed in combination with a nose-piece or sliding objective-changer.
Mounted in tJiis manner, the objectives produce a somewhat higher magnification.

Objective a* (Fig. 7) consists of two achromatic lenses combined after an
original formula of our own computation. By means of a ring RR, rotating like
a correction-collar, the lenses may be brought closer together or separated,
whereby, in combination with an ocular, the magnification can be so greatly
varied that its power is approximately doubled by changing the position of the
index from 0 to division 10 of the scale.

In the year 1890 we constructed the Water Immersion D*. It facilitates the
investigation of living micro-organisms and objects suspended in water at medium
magnifications. Its great working distance gives to the microscopist a relatively
wide range in following the motions of such creatures through both the upper
and lower strata of the water. The peculiar construction of the system tends to
restrict the greatest sharpness of the image to the central portion of the field.

The system may be used with or without cover-glass and gives equally
good images with fresh as with sea water.

For the investigation of fluids by means of the Appliances for the investi-
gation of Ultra-microscopical Particles, is the objective D * particularly adapted on
account of its great free-working distance. See prospectus relating to Appliances
for the investigation Ultra-microscopical Particles (M 164), p. 6.

The Water Immersion Objective PI, an optical combination introduced by
us in 1898 under the designation of the Plankton-Searcher, serves essentially
the same purposes as the system just previously described. Owing to its long focus
this objective yields only low magnifications, and though its aperture is 0.11, it
gives the very large working distance of about 36 mm, and the depth of defini-
tion is considerable. The use of new kinds of glass, capable of resisting the
influence of water, has facilitated a well-nigh apochromatic correction.

To facilitate the use of this objective, we supply a special glass cell
No. 2030 (glass slide with deep glass cylinder cemented thereon), suitable for

use also with the paired objectives (Pl\

Glass cell for PI and

Marks Codeword
3.50 Pajarita

«I»», §cna.

22

List of the Achromatic Objectives.

Combined with HUYREN.

Equi-

Nu-

Ocular 2; Tube-length

Price

De-

valent

merical

160 mm (about 61/, in.)

signation

focal
length

Aper-
ture

Free Work-
ing Distance

Diameter of
visible area
of object

without | with
Correction-Collar

Codeword

mm

mm

mm

Marks

a»

45

—

32

14

12.-

Pajeria

a,

39

—

20

11

12.-

Pajillo

a2

37

—

30

8

12.

Pajonal

Bj

28

—

33

4.5

12.-

Pajiincio

a*

43—29

—

13—53

10—25

40.-

Fajnela

aa

26

0.17

14

4

27.-

Palabra

A

15

0.20

9

2

20.-

Palacial

Dry

AA

17

0.30

7.f>

2.5

30.-

Palaeio

Series

B

12

0.35

3

1.5

30,-

Paladar

C

7

0.40

1.8

0.9

30.-

Pnladino

D

4.2

0.65

0.6

0.5

35.-

Palainallo

DDt)

4.3

0.85

0.4

0.5

( 50.-

Palaiiiciita

l 70.-

Palanca

j 60.

Palainpora

Et)

2.8

0.90

0.25

0.35

\ 80.-

Palani.raiiii

f 75.-

Palatal

Ft)

1.8

0.90

0.17

0.23

i

| 95 —

Falastro

PI

25

0.11

36

4

20.-

Palecer

Water

D*

4.4

0.75

1.5

0.55

75.-

Paloute

Immersion

J

1.8

1.18

0.2

0.23

1 no.-

\

Paletou

I 130.-

Paletero

Homog.
Immersion

12

1.8

1.30

0.15

2.05

125.-

Paliador

For definition of the terms "Free working distance" and "Diameter of visible area of
object" see p. 16.

All these objectives are also supplied adjusted for the English
10-inch body (tube-length 250 mm [about 10-in.]).

With ref/ard to the kind of immersion fluid to be used with
homogeneous immersion objectives refer to pp. 10 and 11.

The Systems DD, E, F contain Fluorite Lenses.

* Paired Objectives for the Binocular Microscopes.

The combinations PI (Water Immersion), 83, 82, 3o and one of still lower
power, namely of 55 mm (about 2V4 in.) focal length, for use with binocular
microscopes, are supplied in a special form of setting and mounted in pairs on
metal slides.

We designate such paired objectives: (55), (a<>), (W), (as), (Plj-

Paired objectives

®

®

©

©

®

Water Immersion

Price: Marks

45.-

45.-

45.-

45.-

55.—

Codeword :

Palido

Palinodiii

Falina

Palmado

Palmear

A pair of suitable diaphragms to slip on, which should be used whenever
it is desired to obtain an image perfectly uniformly sharp up to the margin, is

supplied with each set of paired objectives.

Regarding the use of the paired objectives (Pi) see p. 21.

For tables of magnification, free workiny distance and area of visible field
of the paired objectives Nos 1—4: in combination with the Binocular Microscope,
see p. 2(1.

HUYGENIAN Oculars.

We supply HUYGENIAN oculars for use with achromatic objectives in
five different powers. The various focal lengths of these oculars are serially
graduated so that, with due regard to their peculiar variations in the position of
their lower focal points, the magnifications X 3, 4, 5.5, 7 and 9 are obtained if
the tube-length of 160 mm be maintained throughout.

We make also a HUYGENIAX Ocular 2* with iris-diaphragm similar to the
compensating ocular 4*. What has been said with regard to compensating ocular
4* applies equally to this HUYGENIAN ocular 2*. (See p. 18.)

Regarding oculars for special purposes see under heading of Accessory
Apparatus, pp. 86 — 89.

We would particularly emphasise the fact that HUYGENIAN oculars are designed for use with
achromatic objectives only.

Concerning the employment of achromatic objectives with compensating
oculars, it is to be pointed out that such oculars are only suitable therewith in the case
of objectives of larger num. Ap., O.85 and upwards, i. e., system DD and higher powers.

Seios, cfcna.

List of HUYGENIAN Oculars.

Ocular No.

1

2

2*

3

4

5

Equivalent focus
in mm

50

40

40

30

25

20

Ocular
magnification

4

4

5.5

i

g

Price: Marks:

6.—

6.-

30.-

6.-

6.-

6.-

Codeword :

Palm ula

Palombiu

Palomero

Palota

Palpebra

Palpitar

In subsequent orders for Ocular 2* the factory number of the stand should
be stated.

For the safe-keeping of objectives and oculars, when stored
outside the microscope cabinet, may mahoyany lock-up cases (Fit/. 8)
be had in various sixes, at a price from M 18. — to M 40. — .

Figr. 8.
Mahognny case for objectives and oculars.

Table of Magnifications of the Achromatic Objectives
with HUYOENIAN Oculars,

calculated for a tube-length of 160 mm (about Q1/2 in.) and an image distance

of 250 mm (about 10 in.)

Objectives

HUYUENIAX Oculars

1

2&2*

3

4

5

afl 1 .4

6

10

12

20

a.

7

10

16

20

30

a2

11

15

23

28

41

a3

20

26

38

47

68

a* 3-8

5—12

8-18

10—22

16-33

aa

24

31

46

56

81

A

44

56

78

97

144

AA

42

54

74

91

134

B

63

80

115

140

200

C

100

125

180

220

315

D

175

.220

320

390

550

DO

175

220

320

390

550

E

270

340

495

600

860

F

415

520

760

930

1300

PI

25

33

48

58

84

D*

175

220

320

390

550

J

415

520

760

930

1300

i •

12

420

530

770

940

1320

In employing nose-piece or sliding objective-changer, the length of the nose-piece amounting to
15 mm, that of the sliding objective-changer to 22 mm, must be taken into account (see p. 8).

(Bail

26

Table of Magnifications of the higher powers of Achro-
matic Objectives with the Compensating Oculars,

Objectives

Compensating Oculars

2

4&4*

6

8

12

18

DD

110

220

;i-{()

440

660

990

E

180

360

540

720

1080

1620

F

260

520

780

1040

1560

2340

J

260

520

780

1040

1560

2340

i

12

260

520

780

1040

1560

2340

Table of Magnifications, Free Working Distances and

Diameters of the Area of Objects embraced by paired

Objectives adjusted for Binocular Microscopes,

Paired Objectives

Paired Oculars

1

2.

3

4

Desig-
nation

Free
working
distance
mm

Magni-
fication

Diameter
of visible
area of
object

mm

Magni-
fication

Diameter
of visible
area of
' object

mm

Magni-
fication

Diameter
of visible
area of
object

mm

Magni-
fication

Diameter
of visible
area of
object

Dim

(55)

70

8

13

10

13

13

10.5

15

7.5

©

54 40

without with
diaphragms

13

7.5

16

7.5

23

6.5

28

4.0

©

40

20

5.0

24

5.0

33

4.2

45

3.0

@

30

30

3.3

35

3.2

50

2.7

65

2.0

®

35

35

3.0

42

3.0

58

2.5

72

1.8

N.B. The objectives (PI) may only be used as water-immersion objectives.

Stands.

The general form of stand of "continental" design, which originated in the
type first introduced by G. OBERHAUSER and was subsequently developed by
E. HARTNACK, has undergone many important alterations within the course of
the second half of the past century.

The introduction of the ABBE illuminating apparatus, various new
features in the construction of the stage, and considerable improvement of the
means of focussing mark the material progress which is particularly noteworthy
in the case of monocular stands.

These fundamental changes in the construction of the older universal type
of stand have demonstrated to us the necessity of also modifying our binocular
stands, which we introduced some years ago.

In the last year or two we have made substantial modifications, aiming at
simplification, in the construction of the medium and small stands, and regarding
which, special prospectuses have already been published by us. They deal princi-
pally with the provision made for the subsequent addition of accessories
to stage and illuminating apparatus of the stand in its simplest form,
and at the same time, by avoiding all superfluous luxury of finish in the stand
itself, reducing thereby the price of these stands as low as possible.

A. Illumination of the Object.

I. Illumination by transmitted light.

J D

Modern microscopy relies mainly on illumination by transmitted light, with
a concomitant facility for a wide variation of the incident pencil both as regards
its [angular aperture and its direction. Both these requirements are fully met
by the ABBE Illuminating Apparatus, first introduced by us in 1872 (see
E. ABBE in M. SCHULTZE'S Archiv fur mikrosk. Anatomie, vol. IX, 1873,
pp. 469—480, and Gesammelte Abhandlungen, I, Jena 1904, pp. 101—112). The
use of this apparatus has in the course of the last few decades become so
general, and it has been so universally acknowledged as an indispensable accessory

t33, Stna.

= 28

in advanced microscopic work, that it now justly forms an essential adjunct to
all the larger stands intended for scientific research.

Particulars regarding the construction and L application of tliis apparatus
may be found in the detailed directions for use, which are issued with each
stand fitted with the ABBE illuminating apparatus.

Figr. 9.

a: ABBE Illuminating' Apparatus with ordinary Condenser No. 25'; r: screw for clamping the

condenser in the sliding sleeve; p: knob of iris-diaphragm No. 23; *: ordinary Condenser Xo. 26;

c: Cylinder-diaphragm No. 21. (Full Size.)

The various lens systems — Condensers — which are adapted for use with
the ABBE illuminating apparatus are all mounted in such a manner that they
can be conveniently inserted into the sliding sleeve of the apparatus and may,
if necessary, be clamped in any position. See Fig. 9. Since 1886 we have invariably
added an iris-diaphragm, which facilitates a very gradual variation of the aperture.

We only supply the ARBE illuminating apparatus with one

of the follotving stands : I, III and IV. Its adaptation to other stands

- if at all practicable - - must be carried out in our own works.

The various diaphragms, condensers, &c. used in connection with the appar-
atus are, however, supplied separately as follows:

29

No. 21. The Cylinder-Diaphragm, Fig. 5K A sliding tube fitted with

v5 stops yielding apertures of 1 mm, 3 mm and (> mm diameter.

Xo. 22. The * Iris-Cylinder Diaphragm. In order to obtain a gradual
variation of the illumination when working without a condenser, we have con-
structed the iris-cylinder diaphragm. The laminae forming the apertures
of these diaphragms are arched in the shape of a cupola so that, when the iris is
entirely closed, their edges almost touch the lower side of the object slide.

The cylinder-diaphragm Xo. 21 and the iris-cylinder diaphragm No. 22 can
also be employed in the sliding sleeve of Stand V.

In subsequent orders for cylinder and iris-cylinder diaphragms
the factory number of the stand with which they are to be used
should be stated.

No. 23. The Iris-Diaphragm. The ordinary iris-diaphragm, as always
supplied with the illuminating apparatus, may also be obtained independently.

No. 24. Diaphragms for dark-ground illumination. Since a rational

employment of dark-ground illumination is only possible , when the
dimensions of the stop are exactly adapted to the aperture of both objective and
condenser, the various stops are only supplied to special order.

For the homogeneous immersion systems we will in future supply only a star-disc with
central stops to be suspended in the objective mount above the lenses. Stopping down the illuminating
cone of rays is thus not performed by means of a central stop in the diaphragm carrier, but through
the ordinary iris-diaphragm.

In subsequent orders should be mentioned the objective and condenser for
which the central stops are required. (See directions for the ABBE Illuminating
Apparatus.)

Objectives with correction collars are unsuitable for the employment in
illumination.

Cylinder-diaphragm with 3 stops

Iris-cylinder Diaphragm

Iris-diaphragm for the diaphragm carrier ........

Stops etc. for dark-ground illumination

a) Star-disc with button to support central stop

b) Central stop each

c)- Diaphragms to screw into the mounts of Achromatic ob-
jectives each

d) Diaphragms to slip into the mounts (from above) of Apo-
chromatic objectives each

e) Star-disc with central stop for homogeneous immersion ob-
jectives each

Marks
4.

14-

10.—

Codeword
Pantografo
Pautnflo
Paiizudo

0.50 Papado

1. — Papagallo

O.CO Papalina

1.50 Papanatas

3. — Papasso

= 3o —

Nos. 25 and 26. Ordinary Condenser in sliding tube, No. 25: double
lens formation (Fig. 9a), num. Ap. 1.20, equivalent focal length about 12 mm;
No. 26: triple lens formation (Fig. 9b), num. Ap. 1.40, equivalent focal length
about 8 mm.

Nos. 27 and 28. *Swing-OUt Condenser with iris-cylinder diaphragm.
Fig. 10; No. 27: double lens, and No. 28: triple lens formation.

This form of condenser was introduced by us in 1894 (see Zeitschr. f. wiss.
Mikrosk., vol. XI, 1894, pp. 433 — 440). The apparatus offers the advantage <>f
having the condenser and the iris-cylinder diaphragm combined. Fig. 10. By
the aid of a suitable mechanism the condenser system may be folded clear of
the carrier of the iris-cylinder diaphragm and swung aside so as to facilitate, by
simple means, a change from illumination by mirror and condenser to that by
mirror alone. For details of construction see Directions for Use of ABBE
Illuminating Apparatus.

In subsequent orders for condensers specified under Nos. 25—28
the factory number of the stand should be stated.

Vig. 10.

Swing-out Condenser with Iris-cylinder Diaphragm,

withdrawn from the sliding sleeve and condenser swung out.
(:!/4 Full Size.)

Ordinary Condenser in sliding tube

Double lens formation, num. Ap. 1.20 . . . .
Triple lens formation, num. Ap. 1.40 ....

Swing-out Condenser with Iris-cylinder Diaphragm
Double lens formation, num. Ap. 1.20 ....
Triple lens formation, num. Ap. 1.45 ....

Marks Codnoord

20. — I'apaga
25. — 1'apelear

45.
50.

1'aprleta
Papenro

===== "\ I ==

No. 29. *Centring Achromatic Condenser, numerical aperture 1.0, equi-
valent focal length 14 mm. Fig. 11 p. 32.

In this form of condenser, stopping down the illuminating rays is effected by
means of an iris -diaphragm situated between the lenses, where-
fore the diaphragm of the illuminating apparatus should remain
fully open.

No. 30. *Centring Achromatic Condenser possessing great dis-
tance between its focus and its front lens, numerical aperture and focal
length as above. This form of condenser was suggested by Professor ROLLETT
of Graz. It is specially designed to admit of the use of ZOTH'S cooling trough
which should be placed directly below the object (see p. 93).

The aperture is regulated by means of the iris-diaphragm of the illumin-
ating apparatus.

No. 31. *Centring Achromatic Condenser with enlarged aperture,

numerical aperture 1.30, equivalent focal length 9 mm. By virtue of its large
numerical aperture this condenser admits of the application of an exceptionally
large or of a very oblique illuminating cone, unaffected with the pro-
nounced aberrations invariably present in the cone of rays yielded by ordinary non-
achromatic condensers. The slides used with this apparatus may not exceed a
thickness of about 0.7 mm.

The aperture is here also regulated by means of the iris-diaphragm of the
illuminating apparatus.

Regarding the advantages of the Achromatic Condenser over the ordinary, see our catalogue
relating to Micro-photographic Apparatus, 5th Edition 1903, p. 31.

The Centring Achromatic Condensers Nos. 29—31 are inserted bodily into
the sliding sleeve of the illuminating apparatus from above, and in order
to permit this insertion, the microscope should be canted and the illuminating
apparatus racked well down.

Centring Achromatic Condenser, num. Ap. 1.0, in case .

Centring Achromatic Condenser, num. Ap. 1.0, with great

distance between focus and front lens, by ROLLETT,

in case

Centring Achromatic Condenser, num. Ap. 1.30. in case

Marks Codeword
75. — Papiou

100.— Papula
100.— Paqiiira

ei», cfcito.

HH

OK THE

I UNIVERSITY 1

Vor J

CAI ir^RXVh^

Fig. 11.

Centring' Achromatic Condenser

No. 29. (Full Size.)

Fig. 12.

Centring Appliance for Objective as Condenser
No. 32. (Full Size.)

No. 32. *Centring Appliance for Microscope Objectives used as
condensers. Fig. 12.

In many instances it appears desirable to use achromatic, or also apochromatic, ob-
jectives as illuminators instead of the condensers specified above. For this purpose we
supply a sliding sleeve with centring collar into which such objectives [may be screwed
and which fits into the sleeve of the illuminating apparatus.

No. 34. *ENGELMANN'S Micro-Spectral Objective, for observing the
effect of individual colours of the spectrum upon microscopical objects (see Bot.
Zeitung, vol. XI,, 1882,1 pp. 419—426; also PFLtJGER's Archiv f. d. ges. Physiol.,
vol. XXVII, 1882, pp. 485—490).

No. 35. *ROLLETT'S Spectro-Polariser, as modified by DIPPEL, for
determining the character and degree of double refraction in microscopical ob-
jects (see Zeitschrift f. Instrumentenkunde, vol. I," 1881. pp. 366 — 372, and DIPPEL,
loc. cit, p. 619).

With selenite films for red of the II. and red of the III. order.

No. 36. Centring Appliance for the apparatus under Nos. 34 and 35.

Centring Appliance for Micro-objectives used as Con-
densers

ENGELMANN'S Micro-spectral Objective, in case ....
ROLLETTS Spectro-Polariser, in case

Centring Appliance for apparatus specified under Nos. 34
and 35

Marks Codeword

12. Parabanda

160. — Paradigma

200.— Pnradnra

8. — Parafraste

— 33 —

For Stands V and VI, which are not equipped with the ABBE Illuminating
Apparatus, we supply suitable condensers and iris-diaphragms in another form.
These are as follows:

a. For Stand V.

\<>. 37. *Simplified Illuminating Apparatus with condenser system
num. Ap. 1.20 in sliding tube with centrally fitted iris-diaphragm. It is inserted
into the fixed sliding sleeve similarly as in the apparatus No. 38 and 3805 from
below the stage.

No. 38. *Simplified Illuminating Apparatus with swing-out con-
denser num. Ap. 1.20 and centrally fitted iris-diaphragm. The condenser proper
is the same as in the apparatus No. 41. See p. 34.

Xo. 3805. *Simplified Illuminating Apparatus with condenser system
num. Ap. 1.20 and centrally fitted iris-diaphragm.

To the condenser system or to the iris-diaphragm of apparatus No. 3805
can the under part of the Polariser II No. 161 be attached. See p. 54.

Besides the condensers with centrally fitted iris-diaphragm, specified under Nos.
37, 38 and 3805, there can be also inserted into the sliding sleeve of Stand V the cylinder-
diaphragm No. 21 and the iris-cylinder diaphragm No. 22. On the other hand the achro-
matic condensers, the centring device for objectives, the star-disc and central stops No.
24 a, b for dark-ground illumination, the Polariser No. 160, the apparatus for illumination
with spectral analysed light can not bo used on Stand V.

No. 3810. Iris-diaphragm for the simplified Illuminating Apparatus
No. 3805. We supply this iris-diaphragm also alone, since when employing
Polariser Xo. 161 it can be inserted between the condenser system and the
NICOL'S prism.

Simplified Illuminating Apparatus for Stand V with

ordinary Condenser num. Ap. 1.20

swing-out Condenser num. Ap. 1.20

Simplified Illuminating Apparatus, with Condenser num.
Ap. 1.0, and Iris-diaphragm, for Stand V

Iris-diaphragm of apparatus Xo. 3805 alone

Marks Codeword

80.-
55.—

24.—

8.-

Pural'iiogo
Parairiias

Paraissais
Paraissoiis

34

b. For Stand VK

Similarly as in Stand V there is provided a sliding sleeve below the stag<
in Stand VI a, which, however, has only a diameter of 20 cm. Suitably adaptec
for this sliding sleeve we supply:

No. 39. Cylinder Diaphragm with three stops.
No. 40. *lris-cylinder Diaphragm.

No. 41. Illuminating System, double lens formation num. A p. 1.0. foca
length about 7 mm, with centrally fitted iris-diaphragm.

In subsequent orders for No. 40 or 41 the cylinder-diaphragn
belonging to the Stand should be forwarded.

II. Illumination by incident light.

In the examination of opaque objects, metal specimens, etc., ar
appliance for adequately lighting up the specimens from above is indispensable
If the free working distance of the objective used be very large, it general!}
answers sufficiently well to illuminate the object by the direct rays of daylight 01
lamplight, but, if necessary, the condition of the light may be improved by mean;
of a collective lens placed before the microscope (see under heading of Accessory
Apparatus, p. 91). When, however, the available working distance is small, ar
appliance for passing the light through the objective becomes necessarv. Thi;
requirement is met by the Vertical Illuminator, constructed now by us for ;
considerable time past.

No. 42. *Vertical Illuminator, Fig. 13. The rays issuing from the soura
of light enter through a lateral opening in the mount of the apparatus, strike tin

Cylinder Diaphragm with three stops

Iris-cylinder Diaphragm .

Illuminating system, double lens formation, num. Ap. 1.0,

with iris-diaphragm .-

Vertical Illuminator .

Marks < Codeword

2.— Paralajc
8. — Paralclo

Paralizar
18. — Parainrntu

35

hypotenuse surface of ;i reflecting prism, which covers one half of the aperture
of the objective, and are thence totally reflected through the objective and con-
centrated upon the object

Vig. i:{.
Vertical Illiiiiiinalor No. 42.

A: view of same (partly sectional)

attached to the lower tube and the

objective C — the latter in short

" mount; p: reflecting prism. B: plan

view ; K: milled knob for revolving

the prism.

(Full Size.)

As it is of importance for the efficient working of the apparatus that the upper
lens of the objective should be as close to the prism as possible, most objectives intended
for work with a vertical illuminator should be fitted in special mounts.

Preparations under a cover -glass are not suitable for examination with the apparatus,
unless homogeneous immersion systems are being employed; again, the higher powers
of the Apochromats, 8 mm and upwards, and the Achromats, D and upwards, with the
exception of the homogeneous immersion systems, must therefore be specially corrected
for investigation of uncovered objects.

It is furthermore of great advantage to reduce the diameter of the image of the
source of light so that the illuminated portion of the object may not be greater than
the area of the visual field of the objective used. The: readiest means to attain this
object is by placing the Collective Lens with Iris-Diaphragm No. 201 in the most favour-
able position before the microscope. See Directions for Use of the Vertical Illuminator.

No. 48. An illuminating appliance employing an incandescent lamp, by the
aid of which intense light may be at once directed upon any particular point to
be examined, is provided for use with Stand X°, known under the designation
of the Corneal Microscope. Similar appliances are also applicable to our
other binocular stands (see p. 63).

Illimiinatiim appliance by means of small incandescent

lamps for Stand X, including 3 reserve incandescent lamps

Marks Codeivord
•'{<>. Puraiiffon

«t», Sena.

B. The Stage.

The dimensions of the stages of all our microscope stands, are sufficiently
large to allow of any size of object slide or carrier being used.

The opening of the stage has in most of the stands a diameter of 33 mn
(l*/i6 in.) in order that the large field possessed by the objectives of long focu
may be fully utilised. It may, however, be reduced by the insertion of a dia
phragm (the stage diaphragm) which is supplied with each instrument.

In Stand VI* the diameter of the stage opening is only about 20 mn
(about 3/4 in.).

Revolving Stages are fitted to Stands I and III M ; such stages may be sub
sequently fitted to the other varieties of Stand III as well as to Stands IV and V

Mechanical Stages, i. e., mechanical means of moving the object within th<
plane of the stage in two directions at right angles to each other, may be fittec
to Stands I, III, IV and V.

No. 44. The * Large Mechanical Stage, Fig. 14. The range of th<
movements of this pattern of stage is 50 mm (2 in.) in one direction anc
35 mm (1% in.) in the other; the readings of variations in either direction arc
taken from scales and verniers. (See Zeitschr. f. wiss. Mikrosk., vol. XI, 1894
pp. 301 — 304.) In the latest models a third scale and vernier is added foi
recording the positions of the movable cheek-piece which secures the object slide
This arrangement facilitates the convenient use of the apparatus as a "finder",
and the process of centring is at the same time much simplified by the additior
of a centring-glass an object slide having a cross ruled upon it. (Foi
particulars see the directions for using this apparatus.)

No. 45. Revolving Vulcanite Stage. This stage can be used inter-
changeably with the Large Mechanical Stage No. 44. To effect this the clamping
screw b is removed and the two centring screws unscrewed so far, that the stage

Large Mechanical Stage for Stands I, III and VI ....
Revolving Vulcanite Stage interchangeable with the Large

Mechanical Stage in Stands I, III and IV

Codeword

100.— Paranza

25. — I'arar

37

2(1.

Fig. 14. Large Mechanical Stage, No. 44.

«: lever for securing the lower sliding piece; 6.- clamping screw to arrest

the turning movement.

(% Full Size.)

no longer follows; the stage is then pressed gently forward, raising the hinder
part first and then lifting the stage out of its centring appliance. It should be
observed that, in inserting another stage, the spring steel pin, housed in front
part of the bed, engages in the groove situated in the turning ring of the stage

proper.

i

The stages Nos. 44 and 45 may be inserted into the centring
appliance in the Stands I, III and IV and can, forthwith, be inter-
changeably used one after the other.

*Photo- micrographic Stage. For photo - micrographic and projection
purposes it is particularly desirable to be able to impart a very slow motion to
the object and simultaneously to rotate the stage round the optical axis of the
microscope. Both these requirements are met by our photo-micrographic stage.
It has a diameter of 100 mm (4 in.) and may be moved in two directions at
right angles to each other within a margin of 10 mm (3/8 in.) by means of two
co-axial inilled-heads. The amount of the movements is read by two separate
scales and verniers. Having no centring appliance, this stage is not interchangeable
with the large mechanical or the revolving vulcanite stage.

t

For this reason we supply the photo-mierographic stage only in con-
nection with Stands I C No. 5805 and 5810.

i», Sena.

., o

= 3°

No. 46. *Attachable Mechanical Stage (old pattern). Fig. 15.

The construction of this stage is based in its essential features upon the
principle evolved by Mr. J. MAYALL junr. (see Journal Roy. Microsc. Soc. (2),
V, 122, 1885). Two sliding pieces, mounted at right angles to, and in immediate
contact with, one another, are moved by means of two milled-heads. Their
various positions are recorded by scales and verniers. The range of the lateral
movement is 50 mm (2 in.), that of the movement from front to rear 30 mm
(l3/lti in.). The apparatus may also be used as a "finder" (see directions for
using this accessory).

No. 47. *Attachable Mechanical Stage (new model), Fig. 16.

The milled-heads which cause the movement of the sliding pieces are
co-axial in this pattern of traversing stage and retain their relative posi-
tions in turning. The lateral movement may be effected with
either the right or left hand.

The margin of movement is slightly greater than with the small mechanical
stage, No. 46; the area which can be effectively searched measures about
60 X 30 mm (about 23/8 X !3/i6 in.).

The peculiar mechanism of this stage guarantees a considerably
greater security in the movement of the sliding pieces and
fulfils all requirements of a movable stage when applied to the
purposes of a "finder".

An accurately gauged centring-glass, upon which the divisions of the
crossed line are marked from two edges of the slide, is Jsupplied with each
stage No. 47. (See Zeitschr. f. Instr.-Kde., vol. XX, 1900, pp. 325—327 see also
the directions for using the stage.)

The Attachable Mechanical Stages Nos. 46 and 47 are attached to the
prism flange of the Stand: they are designed for use on our Stands IV A — C and
V A — C Only and can be attached to these Stands without any special adaptation.

No.

1C.

Attachable Mechanical Stage (old pattern)

Marks
85.—

Codeword
Parasite

46"

Case for No. 46

5 —

Parazonio

47

47»

Attachable Mechanical Stage (new model)

Case for No. 47

120.-
5 —

Parcial
Parciduru

39

Fig:. 15.
Attachable Mechanical Stage, No. 46. ('/., Full Size.)

Fig. 16.
Attachable Mechanical Stage, No. 47. (»/,, Full Size.)

— 40 —

Besides the mechanical and revolving stages, auxiliary apparatus serving
the purpose of moving microscopical objects may also be employed.

The Prism Rotator is a suitable accessory to the Binocular Stand Xa and
also to other stands having a stage aperture of 33 mm (about 1 3/a in.) diameter.
The Capillary Rotator may be used in connection with stands having a smaller
stage aperture. (For particulars regarding the above two appliances refer to
pp. 89 and 90.)

For the purpose of determining the amount of very delicate movements
in o n e particular direction, especially where exact measurements of horizontal
displacements are in question, our Stage Screw-Micrometer (see p. 78)
will be found ' useful.

We may here also mention the MALTWOOD Finder (see Zeitschrift f.
wiss. Mikrosk., vol. V, 1888, p. 40), which is an auxiliary appliance for reminding
any particular spot in a specimen under examination. It is a "finder" appliance
of the simplest description and may be used with any of our movable stages.
(See p. 93.)

C. The Focussing of the Objectives.

The coarse adjustment. The whole of the microscope stands specified
in this catalogue are provided with rack and pinion for the coarse adjustment.
We have constructed special machines for the accurate production of the oblique
toothgearing, and this motion is now made in such perfection that even objectives
of medium power can be focussed with sufficient exactness by it alone without
the use of the micrometer-screw.

The fine adjustment. The micrometer movement introduced by us in
1886 (see Zeitschr. f. wiss. Mikroskopie, vol. Ill, 1886, pp. 207—209) has during
this long period been in extensive use and has proved absolutely satisfactory.
We have therefore retained it in the Stands IV, V and VI. The superiority of
this is mainly due to the fact that the force exercised by the micrometer-screw
is transferred to the movable body by a single contact between two hardened
steel surfaces, which ensures an extremely delicate and uniform motion.

In 1898 we introduced an entirely new type of construction of the
upper part of the Stand. The coarse adjustment by means of rack and pinion
was retained, hut the mechanism for fine adjustment underwent a complete
change.

4 1

The then generally used prismatic movement was discarded in favour of
one by means of slides. The sliding piece itself is situated close behind the
coarse adjustment action, with which it is rigidly connected by screws. See Fig. 17.

A worm-wheel, movable by means of an endless screw, is situated at the
lower end of the micrometer-screw and serves in a sense as a screw-head. See Fig. 17.

Here also the force exercised by the micrometer-screw is transferred to the
movable body which carries the tube by a single contact between two hardened
steel surfaces.

The whole mechanism, with the exception of the two milled-heads acting
upon the endless screw, is enclosed inside the crane-shaped carrier
and is thus protected against all direct damage from outside. An additional
safety appliance prevents injury to the micrometer-screw when the sliding piece
has reached the limits of its movement.

29.

Fig. 17.
lti:i;i.i:i:-s Micrometer Movement.

(Full Size.)

Qazt Sews, 3««ct.

42

As the axes of the milled-heads used in the fine and coarse adjustment are
parallel, and as in elevating and depressing the tube both turn in the same
direction, the change from one movement to the other is most convenient for
the hand of the operator.

As regards details of construction we would refer to the article : "Em neuer Mikro-
skop-Oberbau", Zeitschrift fur Instrumentenkunde, vol. XVIII, 1898, pp. 129 — 133.

The divisions on the millcd-head of the old type of micrometer move-
ment, as applied to our Stand IV enables one to read movements of 0. 0 0 5 m m
of the tube in the direction of the optical axis. One of the milled-heads of
BERGER's micrometer movement is also provided with a divided scale, each
division of which corresponds to a variation of 0.002 mm in the posi-
tion o f t h e tube.

By means of above measurements of thickness may be made with a considerable
degree of accuracy. The upper and lower surfaces of the object are successively focussed
and the respective positions of the index read off on the divisions of the milled-head.
The difference between the two readings -- objectives of the dry series being used -
then represents the thickness of the corresponding stratum of air.

If the refractive index of the object be known, its actual thickness may be approxim-
ately ascertained by means of this also. Inversely, the refractive index of an object
may also be approximately determined if its thickness be known. Assuming d = the
difference between the two readings, D = the actual thickness of the object, and ;/ = its
refractive index, then — although approximately only -- the formula

D = nd
holds good.

In, for instance, estimating the thickness of a cover-glass, // mav be assumed to bo
equal to 1.5 without risk of appreciable error.

In taking ""measurements of this kind it is best to use one of the higher dry lenses
and a medium ocular, using central illumination.

With regard to the execution of more exact measurements of thickness by the aid
of the micrometer-screw see an article by S. CZAPSKI on "Die Bestimmung von Deckglas-
dicken an fertigen Praparaten" (Zeitschr. f. wiss. Mikrosk., vol. V, 1888, pp. 482—484).

t

The draw-tube, which is possessed by all stands, with the exception of the
Stands IX, X, XI and the Hand-microscope admits of being increased or diminished ;
the existing tube-length (see pp. 8 and 9) can be read by means of a scale engraved
on the draw-tube, whereby the length of any apparatus -- nose-piece,
objective changer and the like inserted between tube and objec-
tive -- may be duly compensated for (see pp. 8 and 9). The lower end is
provided with the standard screw to take an objective of lower power, as, for
instance, the auxiliary objective used with the apertometer. This standard screw

43

is only absent in the inner tube of the large mineralogical Stand III M ; instead
of a screw thread a slide is made use of, into which the BERTRAND Lens can
be inserted from the outside. (See pp. 50 and 51.)

The internal diameter of our draw-tube is 23.3 mm at the ocular end.

D. Appliances for Changing the
Objectives on the Stand.

Revolving Nose-pieces or Sliding Objective -changers are appliances
designed to facilitate the rapid and commodious interchange, while interfering
as little as possible with the focussing and centring, of the objectives.

The sliding objective changers are in so far superior to the revolving nose-
pieces that they admit of the maintenance of the focussing and centring with
much greater precision than the latter are ever capable of giving. Another
advantage is that in using them the number of objectives is not restricted to
any particular limit.

In using nose-piece or objective-changer, the length of the nose-
piece (15 mm) and that of the objective-changer (22 mm) should
be taken into consideration, and the draw-tube shortened by the like
amount. (See p. 8.)

Nos. 48 — 50. Revolving Nose-pieces, Fig. 18. "A clamping ring with
milled edge serves to fix the nose-piece in any desired position -- as a rule so
as to have the objectives not in actual use turned symmetrically towards the
front. The objectives are screwed into the nose-piece and can by a simple turn
be placed in rapid succession in alignment with the tube, the correct position
being indicated by the snapping of a spring.

A curved cover, turned by special methods of our own, fits closely over
the openings into which the objectives are screwed and protects them against dust.

44

We supply revolving nose-pieces to receive 2, 3 and 4 objectives.

Revolving Nose-piece, No. 48,
for 2 objectives.

u.

Fig. 18.

Revolving Nose-piece, No. 49,
for 3 objectives.

32.

Revolving Nose-piece, No. 60, for 4 objectives.

(Full Size.)

Nos. 52 and 53. *Sliding Objective-changers, Fig. 19. This apparatus
is so arranged that the observer himself may centre each separate objective and
it admits of the use of an unlimited number of objectives.

The tube-slide, No. 52, Fig. 19 a, is screwed on the end of the body like
an ordinary revolving nose-piece and may be secured with the slide action
either pointing to the front or turned sideways.

The plane of the tube-slide is inclined to the axis of the tube at an angle
of about 84°. The plane of the objective-slide, No. 53, is inclined at a cor-
responding angle so that, on being withdrawn, the objective moves slightly
away from the specimen. A screw - - turned by a watch key - - serves as a

Revolving Nose-piece for two objectives

„ three „

„ „ „ „ four .,

Sliding Objective-changer

Tube-slide

Objective-slide, each

Marks
15.-

20.-

25.—

&-

8.—

Codeword
Pardal
Pardiiui
Pardogris

Pareja
Parental

45

fig. 19.
Sliding Objective-changer.

33.

a: tube-slide; b: objective-slide with objective attached; c: in section.
(Full Size.)

centring adjustment in the direction of the slide, while an endless screw (at
right angles to the first-mentioned and, like it, regulated by a watch key) effects
the centring of the objective at right angles to the slide.

Objectives having their mounts so adjusted as to be approximately in focus
when changed can also, by means of the screw-collar on the objective slide, be
accurately focussed and then permanently fixed in their proper position by a
locking nut.

We are prepared, at request, to adjust in our Works with the greatest
care several objectives to be used on a revolving nose-piece or with sliding ob-
jective-changers to one focal plane, with the exception of the systems a, aa, a*
and the immersion systems, if objectives and objective-changers be obtained at
the same time, but we must expressly remark that this adjustment
is accurate only when the correct tube-length is maintained.

Wos. 54 and 55. For the convenient safe-keeping of objectives with ob-
jective-slides attached to them, we supply, when requested, special cases in
various sizes. The most usual forms are the leather case No. 54 for 3 objectives
with their slides, and the mahogany case for 6 objectives with their slides.

Leather case for 3 Objective -slides and Ob-
jectives

Mahogany case for 6 Objective-slides and Ob-
jectives

Marks Codeword

6.— Parhilera

15. — Parida

E. Various Models of Stands.

Large Stands.

Stand I is the ground form of our large stands, and is supplied equipped
with the complete ABBE Illuminating Apparatus, which is arranged so
that all condensers and the like inserted into the sliding sleeve of this Apparatus
may be employed. (See pp. 29 to 32.) The upper part may be inclined so far
that the tube lies in a horizontal position. From the large diameter of the
outer tube Stand I is suitable for Micro-photography and Projection
not merely with the ordinary microscopic objectives but also with the Micro-
planars (see our catalogue relating to Apparatus for Micro-photography and Pro-
jection).

Stand I.

Upper part with BERGER'S Micrometer Movement; wide
outer tube; draw-tube slidable in a tubular sleeve. Tube-carrier provided
with strong handle for lifting the instrument. In lock-up mahogany
cabinet.

We supply Stand I in the following different forms :
No. A: With Revolving Vulcanite Stage No. 45.

5605 Stand I A with ordinary Condenser, num. Ap. 1.40. . . .

5610 Stand I A with swing-out Condenser, num. Ap. 1.40 . . .

B : With large Mechanical Stage No. 44.

5705 Stand I B with ordinary Condenser, num. Ap. J.40. . . .

5710 Stand I B with swing-out Condenser, num. Ap. 1.40

C: With Micro-photographical Stage and the accessories:
Light-excluding Funnel, Adapting Rings for the Micro-
Planars to screw in, Centring Stop, Dark Glass.

5805 Stand I C with ordinary Condenser, num. Ap. 1.40 . . . .

5<S10 Stand I C with swing-out Condenser, num. Ap. 1.40 . . .

1) : The same Stand as I A, but with the accessories spec-
ified under C.

55)05 Stand I D with ordinary Condenser, num. Ap. 1.40. . . .

5910 Stand I D with swing-out Condenser, num. Ap. 1.40 . . .

E : The same Stand as I B, but with the accessories spec-
ified under C.

6005 Stand IE with ordinary Condenser, num. Ap. 1.40. . . .

6010 Stand I E with swing-out Condenser, num. Ap. 1.40 . . .

Marks Codeword

325. — I'ariciitiam

350.— Parietinos

400.— Parilibiis
425.-

415.-
440.-

340.-
365.-

415.-
440.

r.-ii-iiiiicniii
Pari|>|>iiN

Parisiaeos
Paris! tico

I'arjurais
Parlacocco

47

162.

Ffe. 20.
Stand I B, Xo. 5705, with large mechanical stage No. 44.

('/. Full Size.)

Qatt

48

Ifledium Stands.

Stands III and IV but recently introduced are the ground forms of our
medium sized stands. Both are constructed so as to enable subsequent
additions to stage and illuminating apparatus being made.

Avoiding all luxury of finish we have substituted a cast metal foot with
a slightly roughened lacquered surface for the former customary highly turned and
polished foot, and further, for the expensive mahogany cabinet one of polished
alderwood. The mineralogical stand, designated as Stand HIM, which we have
recently fitted with BERGER'S Micrometer Movement, is supplied in a mahogany
cabinet.

Stand III.

Upper body fitted with BERGER'S Micrometer Movement:
Under part with arrangements for subsequent additions to stage and illumin-
ating apparatus. Lock-up polished alderwood cabinet.

We supply Stand III in the following different forms:

No. Marks Codeword
6105 Stand III A, with fixed round stage of 1 1 cm diameter and Cylinder-
diaphragm No. 21 205.— Partout

6205 Stand III B, with stage as in III A and ordinary Condenser num.

Ap. 1.20, together with Iris-diaphragm 235. — Parturio

III A and III B can be supplemented by subsequently adding:

No. 6220. The Diaphragm-carrier 20. — Paruero

6305 Stand III C, with stage as in III A, complete ABBE Illuminating Appar-
atus with ordinary Condenser num. Ap. 1.20 250. — Parusia

6310 Stand III C, but with swing-out Condenser num. Ap. 1.20 275. — Parvale/a
III A, III B and III C can be supplemented by subsequently

adding :

No. 6320. Revolving Vulcanite Stage including centring appliance 42. — Parvonir
No. 6330. Large Mechanical Stage including centring appliance . 117. — Parvient
6405 Stand III D, with Revolving Vulcanite Stage No. 6320 ABBE Illumin-
ating Apparatus with ordinary Condenser num. Ap. 140 . . . 290. — Parvoline
6410 Stand III D, as above but with swing-out Condenser num. Ap. 1.40 315. — Parvulorum
6505 Stand III E, with Large Mechanical Stage No. 633O, ABBE Illumin-
ating Apparatus with ordinary Condenser num. Ap. 1.40 . . . 365. — Parzival
6510 Stand HIE, as above but with swing-out Condenser num. Ap. 1.40 390. — Pasabales

If the Stands III A — III E are not to be supplied in an alderwood but in a maho-
gany cabinet, Marks 2O. — must be added to the prices of the various specifications.

49

y^lHMAw
/ o> THf

UNIVERSITY

or

46.

Fig. 21.

Stand UI B, No. 6205, with Diaphragm-carrier B, Xo. 6220, and its Key (C).

(V, Full Size.)

Stand III M.
Stand for crystallographic and petrographic investigations.

The focussing appliances and tube-carrier the same as in other models
of Stand III; -Draw-tube, with rack and pinion, is at the lower end provided
with slide to admit mounted AMICI-BERTRAND lens through an opening in
the outer tube. In lock-up mahogany cabinet.

Stands III M are furnished with : Polariser I, Analyser - with graduated
circle - - capping the ocular, Analyser mounted slidable immediately above the
objective, Selenite plate Red of the I. Order, Mica plate Y4 ^, Binx-KLEix Quartz
plate ; suitable arrangements are made allowing these crystal plates being inserted
in a sliding-carrier situated above the objective.

The objectives a() and 81 can be used on Stand III M when they are supplied
in a special mount only. (See p. 21.)

Stand III M can be supplied either with revolving and centring vulcanite
stage or the large mechanical stage, both stages being graduated at the
circumference and having line index.

No. Marks Codeword

(J605 Stand III MD with Revolving Vulcanite Stage and ordinary Con-
denser num. Ap. 1.40 500. — Paryadres

(•610 Stand III MD as above, hut with swing-out Condenser num. Ap. 1.40 525.— Par j jrronmi

($705 Stand III ME with Large Mechanical Stage and ordinary Condenser

num. Ap. 1.40 575. — Paryphe

(J710 Stand III ME as above, but with swing-out Condenser num. Ap. 1.40 600.— Purysatis

In the swing-out Condenser num. Ap. 1.40, as supplied for
Stand III M, the two upper lenses are easily detached, since their
mount, not being attached by screwing, simply slips on above the
lowest lens.

To facilitate the employment of Apparatus measuring the angles of axes of
crystals, a piece can be inserted between stage and tube-carrier involving an extra cost
of 8 Marks. Should this insertion-piece be subsequently required to be adapted,
it will be necessary to return the stand to our Works or to one of our Branches.

The compensating ocular 4 and HUYGENIAN ocular 2* can not be used on Stand III M.

163.

Fig. 22.
Stand III MD, >To. 6605 with Revolving Vulcanite Stage.

(V, Full Size.)

No.

6805
6905

7005

7105

7205
7305

Stand IV.

Upper body with the older form of micrometer movement;
under part provided, as in Stand III, with arrangements for supple-
menting the stage and illuminating apparatus. In lock-up pol-
ished alder-wood cabinet.

We supply Stand IV, but very recently introduced, which replaces the Stands I3 ,
II3, IVa and IVb of our former catalogues, in the following various forms:

Stand IV A, with fixed round Stage and Cylinder-diaphragm No. 21
Stand IVB, with fixed round Stage as in IVA, ordinary Con-
denser num. Ap. 1.20 with Iris-diaphragm

To IVA and IVB can afterwards be added to supple-
ment the Illuminating Apparatus:
The Diaphragm-carrier No. 622O

Stand IV C, with Stage as in IV A , complete ABBE Illuminating
Apparatus with ordinary Condenser num. Ap. 1.20 ....

To IVA, IVB and IV C can afterwards be added to
supplement the Stage:

Bevolving Vulcanite Stage, No. 6320

Large Mechanical Stage, No. 633O .

Stand IV D, with centring and revolving Vulcanite Stage No. 632O,
ABBE Illuminating Apparatus with ordinary Condenser num.
Ap. L20

Stand IV E, with Large Mechanical Stage No. 6330, ABBE Illumin-
ating Apparatus with ordinary Condenser num. Ap. 1.20 . .

Stand IV F, with revolving, but non-centring, Stage with graduated
edge, centring arrangement on the tube, ABBE Illuminating
Apparatus with ordinary Condenser num. Ap. 1.20, Polariser I,
Analyser I, Selenite Film for Red of the I. Order No. 180 .

Marks
180-

Codeword
Partirons

•210. Parlitabor

20.-
325.—

42.-
117.—

260.-
335.—

Paruero
Partitciiuir

Parvenir
Parvient

Partitive
Parti THIIO

295._ Partizans

Stand JVF is particularly suitable for histological investigations with polar-
ised light.

Should a swing-out Condenser be desired instead of the ordinary
Condenser the price of the Stand is increased by 25 Maries.

The substitution of a Mahogany Cabinet for that of Alder-
wood raises the price by 20 Marks.

Should a large number of Microscopes be ordered together we
can, if desired, also supply Stand IV without the Alder-wood Cabin-
ets but in ordinary packing case, ivhereby the cost of the indiv-
idual Stand becomes 20 Marks cheaper.

53

Fig. 23.
Stand IV C, No. 7005.

('/, Full Size.)

t«, Sena.

54

No.
7405
7505

7605
7705

Small Stands.

Stand V.

Upper body with older form of micrometer movement, the head
of the micrometer screw is not provided with graduations; the round stage has
a diameter of 11 cm. Stand V does not allow of the complete ABBE Illuminating
Apparatus being adopted, but on the other hand various condensers with centrally
fitted Iris-diaphragm, as well as a Polariser may be inserted into the sliding
sleeve of the stage. The stand can not be inclined. In lock-up polished alder-
wood cabinet.

Stand V, introduced by us in 1904 and especially designed for laboratory
use, is supplied in the following various forms:

Marks

100 —

Stand VA, with fixed stage and cylinder diaphragm No. 21 .

Stand VB, with fixed stage, simplified illuminating apparatus
No. 38O5 with condenser num. Ap. 1.0 . .

Stand VC, with fixed stage, simplified illuminating apparatus
No. 37 with condenser num. Ap. 1.20

Stand VD, with revolving stage provided with graduations at the
margin, objective centring appliance on the tube, Polariser II,
Analyser I and Selenite plate for Red of the I. Order No. 182 170.—

Codeword
Pasacalle

120. — Pasaderas

126.

Pasados

Pasajuego

If the Iris- diaphragm No. 3810, to be inserted above the Polariser in
Stand VD, be desired the price is augmented by 8 Marks. (See p. 33.)

Should a large number of Microscopes be ordered together we
can, if desired, also supply Stand V without the Alder-ivood Cabinets
but in ordinary packing case, whereby the cost of the individual
stand becomes 12 Marks cheaper.

Stand VK

This stand has a fixed stage 80 mm (3l/8 ins.) square. The upper body is
inclinable as far as the horizontal position. It is supplied with the older form
of fine adjustment only, the head of micrometer-screw is not provided with
graduations. In lock-up mahogany cabinet.

Fis. 24.
Stand VA, No. 7405.

('/, Full Size.)

— 56 —

The illumination is obtained by means of the universally movable mirror.
The sliding sleeve fixed below the stage by a bayonet joint is not only adapted
for the cylinder-diaphragm, No. 39, and the iris-cylinder diaphragm, No. 40, but
also the illuminating apparatus, No. 41 (see p. 34), may be inserted.

Owing to its compactness Stand Vla is particulary suitable for a Travelling

Microscope.

We supply the stand, if specially ordered, enclosed in a small leather or
canvas case with shoulder-sling instead of the mahogany cabinet. The total
weight of the stand with complete optical equipment (3 objectives, 3 oculars)
and the most indispensable specimen utensils, also including the case, amounts
to 4 kg (about 9 Ibs.).

No. Marks Codeword

80 Stand VI' with cylinder-diaphragm No. 39 130.— Pasage

81 „ with iris-cylinder diaphragm No. 40 .... 136. — Pasamano

82 „ withilluminatingsystem No. 41 150. — Pasapan

83 Travelling Microscope, Stand VI a, with illuminating system

No. 41, in leather or canvas case with shoulder-sling . . 165. — Pasaporte

Stand IX.

No.
•9105

This stand serves as a useful auxiliary stand for the laboratory, as
well as for technical purposes, especially for the detection of trichinae.

The round stage has a diameter of 100 mm and a large stage opening of 33 mm
which may be reduced by means of the stage diaphragm. The plane and concave
mirror is universally movable. In lock-up polished cabinet.

Stand IX possesses only coarse adjustment by means of rack and
pinion, which permits the use of medium power objectives up to O.Go num.
Ap. Fig. 27, p. 59.

Stand IX in case

Marks Codeword
50. — Pasqiialiim

Stand IX is also suitable for the investigation of opaque objects, rock, metal
surfaces and the like, under lower power magnifications when employing the Vertical
Illuminator. Regarding the use of the Vertical Illuminator, see pp. 34 and 35.

57

£. 25.
Stand IV», No. 82.

(V, Full Size.)

_o

= 5° =

For the particular purpose of detecting Trichinae we supply Stand IX with
specially constructed triple or double-lens objectives, so that by unscrewing one
or two lenses various magnifications result. The two equipments, mainly sufficing
for the above purpose, are as follows:

No. Marks Codeword

9205 Microscope for detecting trichinae I, with triple -lens objective

and two oculars, resulting in six various magnifications between

about 30 and 190 diameters 80. — Pastailora

0210 Microscope for detecting trichinae II, with double-lens ob-
jective and one ocular, resulting in magnifications about 40 and
100 diameters 65.— Pastelada

Both instruments satisfy the enactments in force for the German Empire
with regard to the inspection of carcases. No. 9205 has been specially recom-
mended by Prof. JOHNE of Dresden for the equipment of Inspectors for this disease.
See special prospectus relating to the microscope for the detection of trichinae.

Hand Microscope.

We supply a Hand Microscope (Fig. 26) suitable for class demonstration
The stage, with clips to hold the specimen, is fixed to the sleeve which receives
the body-tube. The instrument is focussed by altering the position of the tube
in the sleeve and after adjustment securing it by a clamping ring. Fine adjust-
ment is effected by drawing the ocular, which fits into the tube with a certain
amount of spring, in or out as required. In using the instrument it is directed
by hand towards a window or lamp.

Fig1. 26. Hand Microscope.

(V, Full Size.)

No.
94 Hand Microscope without objective or ocular, in case

Marks Codeword
15 — Pastilla

59

Fig:. 27. Stand IX.

(V, Full Size.)

6o

Image-erecting Microscopes,

provided with PORRO Prisms.

In the course of 1897 we introduced a new form of binocular microscope
in which stereoscopic vision is obtained, not by division of a pencil of light
passing through a single objective but by a combination of two microscopes,
complete in themselves and provided with erecting prisms.

In the Stands Xa, Xb and X° the double tube is adjustable by means of
rack and pinion.

The application of erecting oculars fitted with PORRO Prisms
affords a convenient means of adjustment for varying inter-pupillary distances.
The paired objectives are mounted upon slides and require adjusting for
each stand separately. Consequently it is necessary to send us the
tube when subsequently ordering paired objectives.

The mount of one of the objectives is provided with screw threads to facilitate equally sharp
focussing of both lenses in cases where inequalities of power of vision in the two eyes require com-
pensating.

We supply paired objectives for these microscopes in five series (see p. 23),

viz: (55), (ao), (a?), (a?) and (pT).

The magnifications obtainable by combinations of the above objectives and
oculars range between 8 and 72 diameters; see tables on p. 26, which also
contain data of free working distances and of diameters of the visible areas of
objects.

It should be observed, that the objective (pf) can only be used as a water immersion
system. (See p. 21.)

The movement of the casings of the PORRO Prisms is sufficient to admit
of adjustment for any inter-pupillary distance within normal limits (56 — 76 mm
= 2l/4 — 3 to-)- In cases where the eyes are abnormally far apart or close together
the actual measurements should be specified when ordering.

6i

V£j«'-«A>..
f O. THF

I UNIVERSITY

or
£*' irCRX'J^

ci.
Fig. 28.

a: Stand X», No. 95. (>/2 Full Size.)
Upper body of Stand X« (as a "Bennatoscope", Ko. 9510) with rnlcanite fork attached.

('/„ Full Size.)

S«J.i», Sena.

62

Stand Xa.

The upper body with the double tube is removable. Fig. 28, p. 61. The

stage forms a square with sides of 100 mm (4 in.) and has an opening of 33 mm
(i5/ie m-) diameter. Hand-rests may be attached at both sides of the stage and
are always supplied with each stand. After removing the upper body a vulcan-
ite fork, which accompanies Stand Xa, may be screwed on to the body-tube
carrier in place of the stage. In this form (Fig 28b) the instrument is available
for objects of any shape and may, for instance, be conveniently used as a
"Dermatoscope" for examining the skin etc., the body carrier being steadied
by the hand.

Instead of the tube-carrier illustrated in Fig. 28a a straight column No. 9520
can be attached upright upon the stage, so that a stereoscopic camera may be
adapted to Stand Xa; the double tube also of Stand Xb can be employed by means
of a column upon the lower part of Stand Xa.

Stand Xb.

This stand, Fig. 29, is primarily designed for the preparation of objects
which are too large to be dealt with on the stage of Stand Xa. It is also ex-
cellently adapted for pond -life studies (whence it may aptly be termed an
Aquarium or Tank Microscope) and for the observation of portions of large
botanical objects, mineralogical specimens, etc., in short, for the microscopical
examination of small areas included within more extensive objects which are not
to be broken up into smaller fragments. The stand is provided with an extra
sliding piece fitted with the "Society" screw which, when in position, closes the
opening of one tube. The other tube may then be employed as a monocular
microscope, the objective in use having first been exchanged for one of higher
power if necessary (see Zeitschr. f. wiss. Mikrosk., vol. XIV, 1897, pp. 5 — 10).

The stand is mounted on a heavy oblong foot and is fitted with 3 rack-
and-pinion and 4 rotary movements. By the appropriate use of these move-
ments every point of an object, however irregular its outline may be, can be
thoroughly examined.

No.

Marks

Codeword

95

Stand Xa with hand-and-arm rests and vulcanite fork . .

195.-

Pastle

9510

Dermatoscope (upper body of Stand Xa with vulcanite fork)

118.-

Pastophore

9520

Straight Column for adapting camera No. 9610 or double-
tube of Stand Xb upon the lower part of Stand Xa . .

10.-

Pastork'ia

Fig:. 29.
Stand X>> with stereoscopic camera and time and instantaneous shutter.

(V4 Full Size.)

Should Stand Xb be also required to be used wich transmitted light, the
stage No. 9605 should be added.

At the suggestion of Dr. DRUNER we have constructed Stand Xb in
such a form that a stereoscopic camera may be immediately substituted
for the double tube. The illustration shows such a camera, with time and
instantaneous shutter, lying at the side of the foot of the stand. For particulars
of the construction and of the manner of using this camera refer to DRtiNER's
"Uber Mikrostereoskopie und eine neue vergrossernde Stereoskopcamera" in the
Zeitschr. f. wiss. Mikrosk., vol. XVII, 1900, pp. 281—293, as well as our catalogue
relating to Micro-photographic Apparatus, 5th Edition, 1903, p. 52.

The illuminating appliance No. 43 (p. 35) can, if desired, be
adapted to Stands Xa and Xb; the prices of the Stands being increased
by such addition by 36 Maries.

Stand Xb, without stereoscopic camera, in alder-wood cabinet
Stage for Stand Xb

Marks Codeword
260.— Pastoso
40. — Pastrana

Qat.1 Sct'», Sana.

— 64 —

Stand Xc.
The Corneal Microscope.

The double tube is similar to that of the two preceding Stands except that an
illuminating apparatus No. 43 is fitted above the centre line of the microscope

so that the optical axes of both tubes are directed upon the same field. This
illuminating apparatus consists of a small incandescent lamp and a duplex
illuminator, both resting on slides so as to be adjustable, thus facilitating the
best possible lighting of the object.

65.

Fig. 30.
Stand Xo No. 98, with EVERSBISCH'S sole-plate and chin-rest No. 9820.

(V5 Full Size.)

= 65 =

As a rule we supply a small incandescent lamp, using a pressure of 7 or
8 volts with a current of I ampere, and 3 spare lamps. For feeding the lamp
it is best to use accumulators. If connection be established with an existing
electrical supply system, sufficient resistance must be provided.

Small incandescent lamps of 12 volt pressure can also be supplied if desired.

The double tube with its illuminator attachment is movable within the
vertical plane by means of a joint which works on a horizontal axis and may
be clamped in any desired position, while a vertical axis admits of the opposite
movement. The microscope is elevated or depressed by means of rack and pinion
and a second similar movement effects changes of position from front to rear.

For fuller details of the construction of this stand see CZAPSKI-. Binokulares
Kornealmikroskop, GRAEF&S Arch. f. Ophthalm., vol. XLVIII, i8gg,pp. 22g—

From a suggestion of Prof. GULLSTRAND we provide, when requested,
Stand Xc with an arrangement for illuminating the object laterally, No. 9810; for
this purpose the illuminating apparatus No. 43 is made slidable in an arc. The
price of the stand with this adaption is increased by 30 Marks.

Subsequent transformation of Stand X° No. 98 is possible so as to embody
GULLSTRAND' s device for lateral illumination; it entails, however, the simul-
taneous ordering of a new cabinet, costing 22 Marks, since any alteration of
the stand will not allow its further accommodation in the cabinet previously
supplied with the simple Stand Xc.

Stand X° resting upon a massive tripod foot is most advantageously employed
when set upon the sole-plate with chin-rest No 9820. At the suggestion of
Prof. EVERSBUSCH this sole-plate is made so as to be movable in two directions
at right angles to each other. The sole-plate with chin-rest can also be employed
with Stand Xc No. 9810 as with Stand X° No. 98.

No.

Marks

Codeword

98

Stand X° (Corneal Microscope) with
apparatus in alder-wood cabinet .

fixed illuminating

220.—

Patache

9810

Stand X° with GULLST RAND'S device for
in alder-wood cabinet

lateral illumination

250.-

Palajrino

9820

EVERSBUSCH'S Sole-plate and Chin-rest
9810

for Nos. 98 and

45.—

Patamar

cw>, Stna.

66

Stand XI.

Monocular image-erecting prism microscope.

Stand XI introduced by us two years ago is particular!}' suitable for use
with the Objective a*. To utilise this system to fullest advantage, the stand has
been constructed to allow an object distance of over 10 cm (4 in.) Stage opening
and mirror have been designed correspondingly large. The stage, 10 cm square,
has an opening 4 cm (iy2 in.) diameter, which can be reduced to one of 2 cm
by means of a stage diaphragm. The universally movable plane and concave
mirror is of 7 cm (23/4 in.) diameter. The under part is for the rest similarly
construct ed[jas that of Stand Xa. Fig. 31.

Fig. 31.
Monocular Prism Microscope. (Y, Full Size.)

No.
9905

Stand XI, Prism Microscope in alder-wood cabinet

Marks Codeword
140.— I'atarafle

= 67 =

The arm carrying the tube can be moved up and down in two different
ways; first, in the ordinary manner by rack and pinion, second, by moving a
slide (carrying the tube along with it) in a dovetail-formed groove. To clamp the
slide a short lever is provided.

The body-tube is provided with an image-erecting PORRO prism-system.
I he lower end of the tube carries the standard thread ; an intermediate ring,
15 mm (s/i6 in.) in length, accompanies each stand, in order to be able to use the
higher power objectives even without nose-piece. The employment of the nose-
piece is, however, to be recommended, since it permits the rapid change from
teasing out and dissection of specimens with low magnifications to observation
with higher magnifications. The intermediate ring should be removed
before attaching the nose-piece.

Respecting details of construction, see: P. CULMANN, Monokulares bildauf-
richtendes Prismenmikroskop, Zeitschr. f. wiss. Mikrosk. XX, 1903, pp. 416—420.

The lower and medium power objectives to D can be used on Stand XI ;
the systems ao and ai, are supplied in a special mount when used with this stand.
A still lower power, 55 mm (2l/8 in.) focal length, costing 15 Marks (Codeword.-
Pataroxa), is likewise suitable.

Our Drawing Apparatus No. 109—112 can be attached to this just as to our
other monocular stands.

Stand Pll.
Drawing Apparatus for low magnifications.

This stand is intended not only for the observation and dissection of large
objects but also to afford facilities for drawing an extensive specimen upon any
desired scale within wide limits.

Two horizontal arms may be moved by rack and pinion up or down the
massive brass column situated on the left. The upper one has a hole bored into
its outer extremity for the insertion of various holders for spectacle-lenses, magni-
fiers and for an erecting microscope ; the lower arm carries a stage frame into
which a plate of glass, metal or wood may be inserted. Fig. 32, p. 68.

Marks Codeword

Stand Pll (Drawing apparatus for low magnifications) in

alder-wood cabinet. Without optical equipment 260.--- I'atescn

Stand P II with drum containing PORRO prism-system, objective a*,
HUYGENIAN oculars 2 and 4, magnifiers Nos. 9 and 10, 4 spec-

tacle-lenses, drawing prism No. 109

410. - Paticojo

= 68

With transmitted light the illumination is provided by a mirror with uni-
versal motions which is inserted into the base-plate or, with very low magni-
fications, simply by means of a sheet of white paper.

The drawing prism, No. 109, slips over the ocular, but if it is to be used
in conjunction with magnifiers or spectacle-lenses, it is fixed to the sides of their
holders.

The drawing board rests upon a frame resembling a desk on the face of
which it slides up or down at an inclination of 25°. The frame itself slides
backward and forward in the groove of the base-plate.

Scales engraved on both sides of the stage in conjunction with a scale on
the base-plate serve to ensure an equal magnification being maintained through-
out the process of drawing selected portions of a large object.

fig. 32. Stand PIT, Drawing Apparatus for low magnifications.

(V, Full SUe.)

= 69 —

The apparatus can also be used for drawing on a reduced scale by placing
the object upon the drawing-board and the paper upon the wooden plate of the
stage.

Objective a* with variable initial magnification is the most suitable lens
for drawing with the microscope although other objectives of low and medium
power, to perhaps C, may still be used with a fair degree of convenience. The
combination of a* with HuYGENIAN oculars Nos. 1 — 5 results in almost any
desired magnification, ranging between X 2.25 and X 23, being obtained, while
the diameter of the visual field varies between about 6 and 45 mm (llt and !3/4 in.).
Spectacle-lenses of from 1 to 5 diopters yield magnifications from 1.25 to 2.25
diameters. For details in construction we must refer to: M. BERGER, Zeitschr. f.
Instrkde. XXI, 1901, pp. 171—175.

1=11=1

Cabinets for the Stands.

The cabinets and cases for the storage and transport of the stands are reduced
as much as possible for the sake of compactness, yet sufficient room is provided
for the entire instrument with its objectives (even when attached to revolving
nose-pieces or sliding changers) and inserted ocular, and for a sufficient number
of objectives, oculars and some few accessory appliances. (See Fig. 45, p. 96.)

The price of the cabinet or case is always included in that of
the stand.

Leather travelling-cases for the protection of the cabinets are regularly
manufactured by us in two various sizes.

Marks Codeword

Leather travelling-cases for cabinets of Stands I, III, IV ... 36.— Patrissabo

„ Stand VI8 38.— Patrizzavi

If desired, the owner's name may be engraved upon the base of the stand.
Charge for engraving name on stand: Marks 3. — . (Code-word: Patriota.)

Mckelled name plates for the mahogany cabinets are also supplied. Price
of nickelled plate, including engraving of name: Marks 5. — . (Codewyd: Patricio.)

Accessory Apparatus.

A. Drawing Apparatus.

The drawing surface in all drawing apparatus of our make is rendered
visible by double reflection, while the pencils of rays emerging from the micro-
scopes or magnifiers reach the eye by a direct path.

In addition to the old form of "Camera hicida" - the drawing prism.
No. 109, shown in Fig. 33 and introduced by us in 1869 — the drawing apparatus
designed by Professor ABBE has been supplied by us for about the last 20 years.

For a special Drawing Apparatus for low maf/nificationx see

pp. 67 — 69.

While in the drawing prism, as also in most other existing forms of drawing
apparatus, only a semi-circular portion of the exit pupil can be utilised, in the
ABBE drawing^ camera the full area of the pencil is effective. Loss of light
is therefore avoided even when using the highest magnification,
while both the pencil and the drawing surface remain quite clearly visible. This
material advantage is gained by the application of a small cube, composed
of two equal rectangular prisms cemented together -- the "ABBE cube"
in the position of the eye-point of the ocular. The cemented surface of the
upper prism is silvered but has a central aperture of 1 or 2 mm diameter.

The brightness of the drawing surface and of the image can be modified

in all our drawing apparatus by the interposition of smoked glasses. With
drawing prism, No. 109, as also with the small ABBE drawing ap-
paratus, No. 110, one or two smoked glasses may be inserted into the prism
casing. The .brightness of the image may be moderated in either of two ways,
i. e., by appropriate stopping or by the use of smoked glasses in connection
with the illuminating source.

For the purpose indicated above the large ABBE drawing apparatus,
Nos. Ill and 112, are fitted with a cap encasing the prisms from above, which
is provided with moderating glasses of varying degrees of
illumination, and with a similarly equipped eccentric disc pivoted
below the prisms. In both appliances only five of the six openings contain
smoked glass, the sixth remaining clear so that the cap and disc may remain

attached although the brightness of the image or of the drawing surface may
not require moderating.

In order to enable the somewhat large exit pupil of the microscope obtained
with low magnifications being fully utilised, the usual ABBE cube with aperture
of 1 mm can, with the two large drawing apparatus, quickly and conveniently
be exchanged for another of 2 mm aperture.

Glasses to correct defects of vision are, if required, supplied with our drawing
apparatus.

No. 109. *Old form of Camera lucida. This drawing prism is only
supplied in the form shown in Fig. 33. The prism casing turns round a hori-
zontal axis and is also adjustable in elevation. It is attached to the tube by
means of a sprung collar and can easily be turned aside.

75.
Fig. 38. Drawing Prism (Camera lucida) No. 109. (3/4 and 2/1 Full Size.)

On the Drawing Apparatus for low magnifications (Stand Pll), No. 102

can only the drawing prism No. 109 be used. For the arrangement of this ap-
paratus, which can be equipped at the same time with an image-erecting micro-
scope, see pp. 67—69.

The ABBE drawing cameras are constructed in three different forms:

No. 110. *Small ABBE Drawing Apparatus. The prism casing and

the mirror — the latter supported by an extended arm about 105 mm (4 in.) long -
are connected with the clamping ring by hinges. The size of the mirror is
50 X 75 mm (2 X 3 in.). The clamping ring is attached to the draw-tube before
putting on the ocular. The upper parts -- prism casing and mirror — can be

Drawing Prism (Camera lucida), in case
Small ABBE Drawing Apparatus, in case .

Marks

81 —
30.-

Codeword

Patron

Patronato

Qatt

— 72 —

turned back on their hinges so as to enable the object being viewed direct
instead of through the prism. The ABBE cube and other parts always return to
exactly the same position on being closed down again.

Fig. 34. Small ABBE Drawing Apparatus, No. 110. ("/., Full Size.)
Tl

Fig. 35. Large ABBE Drawing Apparatus, No. 111. (3/r, Full Size.)

No. 111. *Large ABBE Drawing Apparatus. After removing the
ocular the clamping ring of the drawing apparatus is slipped over the tube and

No.
Ill

Large ABBE Drawing Apparatus, in case

Marks Codeword
60.— Patiido

73

fastened by tightening the screw 6". By altering the position of the clamping ring
the aperture in the silvered prism may be brought to the same height with the
exit pupil of the microscope. The screws L and H (Fig. 35) serve to facilitate
the accurate centring of the prism. (See Zeitschr. f. wiss. Mikrosk., vol. XI, 1894,
pp. 28!) — 298, as well as the directions for use accompanying each ABBE drawing
apparatus.)

The length of the supporting arm and the size of the mirror are the same
as with the preceding apparatus. The casing, together with the prism and the
moderating glasses, may be turned aside about the pin Z into the position indicated
by the dotted lines in Fig. ;>f>.

No. 112. *Large ABBE Drawing Apparatus. This form of the apparatus
is adapted for the oculars with enlarged field of view but it can also be used
with ordinary oculars. The length of the arm supporting the mirror is 125 mm
(5 in.), the size of the mirror 80 X 125 mm (3yg X 5 in-)-

Drawing Tables and Boards.

In order to obtain copies of objects free from distortion and with a field of
view of fair size, it is advisable to use a support for the drawing paper, inclined
at the proper angle. We supply various patterns of drawing tables and boards
suitable for this purpose.

Nos. 113 and 114. The two forms of *BERNHARD's Drawing Tables satisfy
in a perfect manner the twofold requirement of being adapted for regulating the
height of the drawing surface above the work table and for varying its degree
of inclination to the horizontal plane. (See Zeitschr. f. wiss. Mikrosk., vol. IX,
1892, pp. 439—445, and vol. XI, 1894, pp. 298—301.)

With tables of above pattern the drawing surface may be raised to a height
of 17 cm (63/4 in.) and inclined at an angle of about 35°. The microscope is
clamped to the base of the drawing table, and arm-rests are provided in order
to give the operator's hands the steadiest possible position.

Xo.
112

118
114

Large ABBE Drawing Apparatus (for oculars with enlarged

field of view), in case

BERXHARD'S Drawing Table, for use with erect Microscope
BERNARD'S Drawing Table, for use with inclined Micro-
scope

Marks Codeword

72 Paulatino

45. — Pausado

52. — Pantador

Qazt

74

The table is supplied either for use with the microscope in the upright
position (No. 113) or with an arrangement for inclining the microscope (No. 114),
together with the table. (Fig. 36.)

Fig. 36.
BERKHARD'S Drawing Table No. 114, in combination with Microscope and Drawing- Apparatus.

('/„ Full Size.)

No. 115. In addition to above-described two patterns of drawing tables we
also!] supply suitable lime-wood Drawing Boards, No. 115, having the surface
inclined at an angle of 25°.

*No.
115

Simple Drawing Board .

Marks

2.50

( Codeword
Parana

75

B. Appliances for measuring and counting
microscopic objects.

fJeasuring apparatus.

Ocular Micrometers and Stage Micrometers.

The requirements of measuring microscopic objects are in most cases met
by the use of simple ocular micrometers, i. e., of small glass discs with divisions,
which are dropped into the oculars with the side bearing 'the division lines
downwards. The values of divisions are best determined by comparison with a good
stage-micrometer for each combination of objective and ocular. Approximate
values, which are in many cases sufficiently accurate, will be found in tables
supplied with each ocular micrometer. These tables apply to combinations of
achromatic objectives with HuYGENIAN oculars, and are calculated for the pre-
scribed (160 mm) tube-length.

In combinations of the compensating oculars 6 with any of the apo-
chromatic objectives the approximate determination of the value of an interval
becomes very much simplified. The divisions in this ocular are so computed
that with a tube-length of 160 mm the value of one interval of the micrometer
scale represents exactly as many micra, /< (0.001 mm), as there are millimetres in
the focal length of the objective, i. e., Systems: 16 mm, 8 mm etc., value of inter-
val: 16 «, 8 n etc. (See Zeitschr. f. wiss. Mikrosk., vol. V, 1888, pp. 150—155.)

As however these values also are still only approximate, a comparison
must be made with the stage-micrometer whenever more exact measurements
are required.

Our regular manufacture of Ocular Micrometers is restricted to the
one form, catalogued as No. 117 : 5 mm divided in Vio mm.

Other divisions to order.

When ordering ocular micrometers please state whether they are required
for ordinary or for micrometer oculars.

Ocular Micrometer, in case

Marks Codeword
5. — Paviloii

= 76 =====

Two forms of Stage Micrometers are regularly supplied:

No. 118: 1 mm divided in 100 parts.

No. 119 : 1 cm divided in millimetres, the last of which in tenths.

With regard to ocular and stage cross-line micrometers refer to p. 80.

Fig:. 37.
Micrometer Ocular.

(Full Size.)

Nos. 120— 123. Micrometer Oculars. Oculars
sliding eye-lenses, "micrometer oculars", are constructed
for the purpose of facilitating exact adjustment of the
micrometer scale to the eyes of individual observers.
These are the HUYGEXIAN oculars 2 and 3 (Xo. 120) for
achromatic, and compensating ocular 6 (No. 122) for apo-
chromatic objectives. The upper part of the ocular-tube
is capable of being unscrewed so that the ocular-micro-
meter can be conveniently laid upon the diaphragm.

By fitting a drum-shaped adapter to these micrometer oculars lateral
adjustment of the micrometer scale, or of, an index (see under Index Oculars,
p. 88), becomes also possible. When thus fitted, they are called "Drum Oculars
with Micrometer" and may also consist of either the HUYGENIAN oculars 2 or 3
(No. 121) or compensating ocular 6 (No. 123).

No.

118
119

120
121

122
123

Stage Micrometer, in case

Micrometer Oculars for Achromatic Objectives:

HUYGENIAN Ocular 2 or 3 with micrometer . .

„ „ „ „ „ „ D r u m a n d S c r e w

for moving the micrometer laterally, called

the "Drum Ocular with Micrometer", in case . . .

Micrometer Oculars for Apochromatic Objectives :

Compensating Ocular 6 with micrometer. . .
„ „ „ „ DrumandScrew

for moving the micrometer laterally, "Drum
Ocular with Micrometer", in case .

Marks Codeword

10. — Paviiniento

6.— Pavon

18.— Pavonazo

40. — Pavorde
31.— Pavura

53. — Payaso

77 =

No. 124 or 125. *Screw Micrometer Ocular. This apparatus is for per-
forming very exact measurements. It consists of a RAMSDEN ocular of about
20 mm (3/4 in.) focal length — corresponding magnification = = 12 diameters — or
a suitable compensating ocular and a very carefully constructed micrometer with
divided drum. (Fig. 38.) The glass plate, with a crossed as well as a double
line, is moved across the field by means of the micrometer screw. Each interval
of the divided drum corresponds to a movement of 0.01 mm of the point marked.
Complete revolutions of the drum are counted by means of a numbered scale
seen in the field. The measurement can be extended over a tract of 4 mm of
the objective image.

The absolute values corresponding to the divisions of the drum should be
determined by the aid of a stage-micrometer for each separate objective.

Fig. 38. Screw Micrometer Ocular, No. 124.

Sectional elevation and plan view. (*/3 Full Size.)'

Screw Micrometer Ocular with RAMSDEX ocular for
achromatic objectives, in case

Screw Micrometer Ocular with compensating ocular 6
for apochromatic objectives, in case

Marks Codeword
90 — Peal
105. — Pebetero

Qa.it /&iitt, Sena.

— 78 —

Xo. 126. *Stage Screw Micrometer. For the exact measurement of
objects too large for inclusion in one visual field of the microscope we construct
the Stage Screw Micrometer. A slide moved by the micrometer screw carries
a rotating disc with divided cirde. The divisions of the drum indicate 0.002 mm ;
complete revolutions of the drum are counted by an index. The screw measures
up to 10 mm.

The instrument is adapted for Stands I, III, IV and V. In subsequent orders
the factory number of the stand should be quoted.

Fig. 39. Stage Screw Micrometer, Xo. 126. ('/3 Full Size.)

Nos. 137 and 128. Goniometer Oculars. For measuring the angles of

microscopic objects we construct the Goniometer Oculars, the former number
with .HUYGENIAN oculars 2 or 3 (Xo. 127), the latter with compensating
ocular 4 (No. 128). The eye-lens is adjustable as with the micrometer oculars.
A glass disc with a series of parallel lines ruled upon it rests upon the diaphragm.
An indicator, attached to the upper part of the ocular, moves within a divided
circle fixed on the draw-tube.

Xo.
126
127
128

Stage Screw Micrometer, in case

Goniometer Ocular, HUYGENIAN ocular 2 or 3

Goniometer Ocular, compensating ocular 4 .

Marks Codeword

120— Pecable

35. — Poeante

48. — Peceniento

79

Appliances for measuring thicknesses.

Xo. 12',). Dial Cover-glass Gauge. The apparatus serves the purpose
of estimating the exact measurement of the thickness of cover-glasses, thin
plates, etc. - • The measurement is effected by means of a clip projecting from
a box-shaped round casing. The reading is given by an indicator moving over
n divided circle on the lid of the box. The divisions show hundredths of a
millimetre. The gauge measures thicknesses up to 8 mm.

Xo. 130. Cover-glass Gauge of simpler construction. This instrument
consists mainly of a screw with divided drum and, like the preceding, records
readings of 0.01 mm.

Measuring Scales and fully divided Circles.

Xos. 131 to 139. We are prepared to supply measuring scales on
nickel-silver Or plate-glass in any form desired. The following are a few
patterns regularly stocked by us:

The nickel-silver rules have bevelled edges. In rules on plate-glass and in the
fully divided circles the figures are in mirror-type so that the divisions may be laid
on the surface of objects to be measured and be easily read off without parallax.

138
13!)

Dial Cover-glass Gauge

Cover-glass Gauge, simpler construction

Nickel-silver Rule, 10 cm divided in millimetres . . . .

Rules on Plate-glass with simple ruling:

5 cm divided in ljt millimetres

10 „ „ „ millimetres

20 „ „ „ „

30 „
Rules on Plate-glass, double scale (one side in millimetres,

the other in inches):

5 cm in half millimetres (2 ins. in 48 parts) . . . .
10 cm in whole millimetres (4 ins. in 48 parts) . . .

Fully divided Circles on Plate-glass:

Circle of 80 mm diameter divided in degrees . . .
„ 120 „ „ „ „ half degrees. .

Marks Codeword

30— Pecora

15. — Pectoral

4. — Pecunia

3.—
^

8.—
12.—

4.50
6.-

14.—
20.—

Pedaceria
Pedagogo
Pedano
Pedestal

Pedldo
Pediluvio

Pedometro
Pedrada

8o

appliances for Counting.

Cross-line Micrometers are usually employed for counting small objects,
such as blood-corpuscles, yeast-cells, bacteria, etc.

No. 140. Ocular Cross-line Micrometer. We supply this micrometer
to rest on the diaphragm of the ocular or, preferably, for use with a micrometer
ocular having an adjustable eye-lens. The division embraces a square of f> mm.
divided into squares of 1.0 or 0.5 mm, as may be desired.

When ordering please state whether the "micrometer scale is required for
an ordinary or for a micrometer ocular.

Xo. 141. P. EHRLICH'S Ocular-diaphragms may be used for counting
the number of corpuscles within a field of known area, in a similar manner as the
ocular cross-line micrometers. These diaphragms are provided with square openings
and are supplied in assorted sets having squares of 1, 2, 3, 4, 6, 8 and 10 mm.

In the case of ocular cross-line micrometers as well as EHRLICH's diaphragms

- unless the latter are merely intended for verification of the quantities within

the same area -- it is necessary for each combination of objective and ocular to

ascertain, by means of stage micrometers, the actual surface values corresponding

to the various fields.

EHRLICH'S diaphragms being primarily designed for use in conjunction
with micrometer oculars (see p. 76), it should be expressly stated when ordering
them if they are to be used with other types of oculars.

No. 142. CrOSS-line Stage Micrometers are, as a rule, supplied only in
connection with the appliance known as the *Counting Chamber. This latter
consists of a cell of exact and uniform depth of 0.1 mm, the bottom of which is
ruled in squares. The most commonly used form of such chamber (THOMA's) —
No. 142 -- contains 400 squares, each having an area of Y^o square millimetre.

Two cover-glasses, • plane-polished, of 0.4 mm and 0.6 mm, accompany each
counting chamber.

No.
140

Ocular Cross-line Micrometer, in case

Marks Codeword
5. — Pcdregwio

141
142

P. EHRLICH's Ocular-diaphragms, 7 pieces in all . . . .

THOMA'S Counting Chamber (Cross-line Stage Micrometer)

with 2 cover-glasses in case

10.— IVdril
15.— Pedro

— 8i =

Besides the counting chamber No. 142 we supply various other counting
chambers as well as accurately calibrated mixing pipettes for diluting blood and
the like.

No. 149. Blood-COUnting Apparatus, consisting of a counting chamber
and one or two accurately calibrated mixing pipettes, is likewise supplied in
various combinations. THOMA's Haemocytometer, No. 149, supplied with one
mixing pipette for red corpuscles and another for the white, is the most frequently
used apparatus of this kind.

Further information regarding the variety of forms of the
divisions of squares in our counting chambers, the various classes
of mixing pipettes and complete counting apparatus are contained
in a separate pamphlet dealing with blood-counting apparatus
(M 10), copies of which may be obtained on application.

Marks Codeword

THOMA'S llaeinocytomcter (Blood-counting Apparatus),

No. 142. with '2 mixing pipettes, in case .

30.— Peira.\o

C. *Apertometer, *Test-plate, * Diffraction Apparatus.

Nos. 155 and 156. Apertometer. A simple apparatus for determining the
numerical and angular aperture of objectives, the Apertometer, was designed
by Professor ABBE in 1876. It is adapted for any large or medium stand fitted
with a draw-tube. A low-power objective of about 40 mm focal length, which
screws into the lower extremity of the draw-tube, is supplied with the instrument,
but under appropriate stopping the BERTRAND lens may, with Mineralogical
Stand HIM, be used instead. The auxiliary microscope, formed by the combin-
ation of the low-power objective with the ocular, being focussed upon the exit
pupil of the objective to be examined, the numerical aperture of the latter i may
be read off from the apertometer by means of two movable metal indicators.

Further particulars regarding principles of construction of the apparatus
and the method of measuring with it are contained in the Journ. of the R. Micr.
Soc. (1), vol. I, 1878, pp. 19—22, and (1), vol. Ill, 1880, pp. 20—31; E. ABBE,
Gesamm. Abhandl. I, 1904, pp. 113—118 and pp. 227—243; see also DIPPEL,
"Das Mikroskop", vol. I, pp. 348—352.

i«, cfctta.

— 82

We supply two different patterns of the apertometer; in the form (No. 155)
shown in Fig. 40 the indicators move upon the glass disc direct, whereas in the

View from above.

Fig. 40.
Apertometer, No. 155.

(Full Size.)

Side view.

second model (No. 156) the glass disc is mounted upon a metal plate with a
slot for the more certain and more convenient adjustment of the indicators.

No. 157. Test-plate. For testing lenses with respect to spherical and
chromatic aberrations and for estimating the thickness of the cover-glass, which
corresponds to the most perfect correction, a test-plate was designed by ABBE
in 1873. Used in conjunction with the ABBE Illuminating Apparatus and by
establishing the sensitive rays, it gives the greatest prominence to any existing
faults of correction.

This test-plate consists of an object carrier with six cover-glasses of accur-
ately determined thickness (0.09 mm to 0.24 mm) cemented side by side. These
cover-glasses are silvered on their lower surfaces and engraved with lines, the
jagged edges of which form the test-object proper.

*

See E. ABBE in Archiv f. mikr. Anat, vol. IX, 1873, pp. 434—437, Ge-
sammelte Abhandl. I, 1904, pp. 66—68, also DIPPEL, "Das Mikroskop". vol. I,
p. 340, and the directions accompanying the test-plate.

No.
155

ABBE's Apertometer, in case

Marks

70.-

Codeword
Polar

15<>

ABBE'S Apertometer, with slot-guide for the indicators,

in case

90.—

Polaza

157

ABBE's Test-plate, in case

10.-

Peleador

Xo. 158. Diffraction Apparatus. Constructed by ABBE in 1876 it serves
to demonstrate the effects of diffraction in the formation of microscopical images.
It consists of a diffraction-plate and a set of stops, with an arrangement for
fitting and rotating them above the objective.

The dimensions of the stops are only adapted for the ob-
jective aa.

No. 15!). Diffraction Plate. This plate consists of a glass slide with three
cover-glasses cemented side by side. The lower surfaces of the latter are silvered
and have groups of lines ruled upon them so as to form various simple and
crossed gratings.

See Monthly Micr. Journ., vol. XVII, 1877, pp. 82—88 ; DIPPEL, "Das Mi-
kroskop", vol. I, pp. 147 — 156; ZIMMERMANN, "Das Mikroskop", Vienna, 1895,
pp. 46 — ;f)l.

1=

D. Appliances for microscopic examination
in polarised light.

Nos. 160 and 161. Polarisers. As a rule we supply polarisers with end-
surfaces inclined to the optical axis of the microscope. That having an aperture
of 10 mm, Polariser I, No. 160, is intended for use with Stands I, III and IV.

Selenite and mica films may be placed upon the plate-shaped rim of the mount.

The other form of 8 mm aperture, Polariser II, No. 161, is as a rule
supplied only for use with the double-lens condenser system, num. Ap. 1.0 for
Stand VD.

The iris-diaphragm No. 3810 of the simplified illuminating apparatus No. 3805
(see pp. 3;» and 54) can in Stand V D be inserted between the condenser system
and Polariser II.

In subsequent ordering Polariser
number of the Stand should be stated.

II, No. 161, the factory

No.
158

ABBE'S Diffraction Apparatus . . ' . . ....

Marks

20.—

Codeword
Pelele

15!)

., Diffraction Plate alone, in case

8 —

Pdicabra

160

Polariser I, for use with Stands 1, III and IV

22.—

Peliciila

lt',|

9, II, Stand VD

25.—

Pelito

— 84

Nos. 162 and 163. Analysers. The Analysers supplied by us are, as a
rule, prisms of 6 mm aperture with their top and bottom faces at right
angles to the microscope axis. The mount of Analyser I is so arranged
that the prism fits immediately upon the ocular. Analyser II is fitted with a
divided circle attached to the tube, above which the prism revolves.

Nos. 165 to 168. *ABBE's Analyser-Oculars. In addition to the above we
supply the ABBE Analyser-Oculars. These consist of an analyser of special
construction situated between the lenses of HUYGENIAX ocular 2 (Xos. 165 and 166)
or compensating ocular 4 (Nos. 167 and 168). The oculars (Nos. 166 and 168),
too, may be fitted with divided circles.

Nos. 169 to 174. Combinations of Polariser and Analyser. For con-
venient safe-keeping we supply various combinations in special cases.

In subsequent ordering No. 173 or 174 the factory number of the Stand
should be stated.

•

If one be already possessed of a divided circle, as, for instance, that supplied
with our Goniometer Ocular, it can be adapted to take the Analyser. In this
case a charge of 3 Marks, over and above that specified for the combination
without divided circle, is made, for supplementing and adapting the mount of the
Analyser to the existing divided circle. The divided circle must be forwarded
us for this purpose.

No.
162

Analyser I .

Marks

15.

Codeword
Pelmazo

163

II, with dividedcircle

30.-

Pelon

165

Analyser-Ocular I for Achromats

40.-

Pclotear

166

„ „ II „ „ with divided circle .

65 —

Peloton

167

Ill Apochromats

58-

Peltre

168

„ IV „ „ with divided circle

68.-

Peluca

Combinations of Polariser and Analyser.

A. for Stands 1, III and IV:

169

Polariser I and Analyser II

58.—

Pehisilla

170

I I

41.—

Pcna

171

I ABBE'S Analyser-Ocular 11

88 —

Penador

172

I I .

66.-

Pennine

B. for Stand V:

173

Polariser II and Analyser II

61 —

Peucazo

174

II I

44.—

Pendado

= 85 =

No. 177. Axial-image Ocular. With the large Mineralogical Stand HIM

a BERTRAM) lens forms the objective of an auxiliary microscope for observing
axial images. For the same purposes we provide a special auxiliary, the Axial-
imagc Ocular, to be used in conjunction with our other stands.

No. 178. *lris-diaphragm with Ocular. For examining and accurately
identifying the axial images of small crystals we supply Iris-diaphragm with
Ocular which fits into the tube.

See special prospectus relating to appliances for investigation with
polarised light.

Nos. 179 to 182. Selenite and Mica Films. We supply regularly four
selenite films Red of the I, II., III. and IV. Order; also four different mica
films Vs A- V* A. 8/8 A and 1/s I. These 8 films compose the set of selenite and
mica films originally proposed by H. v. MOHL, No. 179.

We supply these films in cardboard mounts for laying on Polariser I No. 160
or in a metal mount for laying in the slide of Stand III M or for insertion between
Analyser and Ocular.

A Selenite Film for Red of the I. Order generally meets all
requirements.

Axial-image Ocular

Iris-diaphragm with Ocular, to fit the tube

MOHI/s Set of Films, mounted in cardboard

Selenite Films, Red of the I. Order, for Polariser I .

I. „ for the slide of

Stand III M . .

„ „ „ „ „ I. „ for insertion be-
tween Ocular and Analyser

Marks

80.—

25.—

15.-

3.—

Codeivord

Pendola

Pendra

Peueque

Penetrar

Penible
Peninsula

Selenite Films of other orders, in cardboard mounts, each 2 Mks., in metal
mounts, each 3 Mks. ; Mica Films, in cardboard mounts, each 1.50 Mks., in metal
mounts, each 2.50 Mks.

Regarding other crystal films for similar purposes we must refer to the
special prospectus relating to appliances for investigations with polarised light.

(Bait

86

E. Miscellaneous Accessory Apparatus.

Oculars for special purposes.

No. 189. *ABBE'S Stereoscopic Ocular. Fig. 41. This apparatus is

designed for stereoscopic as well as ordinary binocular observation of microscopical
objects with any desired magnification. (See CARL'S "Repertorium". vol. XVII.
1881, pp. 197—224; also Journ. of the R. Micr. Soc. (2), vol. I, 1881, pp. 203-211;
E. ABBE, GesJAbhdl., vol. I, 1904, pp. 244—272.)

n.

Fig. 60. ABBE'S Stereoscopic Ocular, Xo. 189. ('/'., Full Size.)

The division of the pencil of rays emerging from the objective, with the
object of producing two separate images, is effected at the upper end of the
tube by partial reflection at a thin stratum of air between the two prisms a and b.

No.
189

»
ABBE'S Stereoscopic Ocular, in case .

Marts Codeword
180 — Peonia

= 87

The bisection of the pencils for producing stereoscopic effect is made by
adjustable semi-circular stops placed over the oculars, without these, i. e., with
full}' exposed oculars, the instrument gives binocular vision without specific
stereoscopic effect.

The distance between the oculars is adjustable - by altering the position

<>f one of the ocular tubes -- to suit the inter-pupillary distance of any individual

.observer's eyes. The instrument is available (but in conjunction with achromatic

objectives only) for use on any of our large stands in which the tubes admit of

shortening to at least 140 mm (5'/2 in.).

Xo. UK). *ABBE'S Spectroscopic Ocular (Micro-Spectroscope). Fig. 42.

This ocular is specially designed for the examination of the absorption spectra
of microscopic objects, but is also adapted for spectroscopic analysis of larger
objects, liquid strata, etc.

The achromatic eye-lens is accurately adjustable with respect to the slit
situated in the plane of the diaphragm. By a lever arrangement a comparison
prism can be applied to the slit to facilitate spectroscopic comparison of the object
with other absorption media, which are attached in suitable holders at the side of
the ocular. An assortment of small glass tubes is supplied for this purpose.

93. 94.

Longitudinal section of the whole instrument. Slit mechanism separately.

'('/„ Full Size.) (Plan view; Full Size.)

Vig. 42. ABBE'S Micro-Spectroscope, Xo. 190.

A direct-vision AMICI prism, which may be turned aside about a pivot,
is placed above the ocular. A scale of wave-lengths is projected upon the

ABBE'S Spectroscopic Ocular (Micro-spectroscope), in case

Marks
200.—

Codeiuord
Peorus

c t:>^ ore-net.

00

oo

spectrum by means of a tube, with mirror and lens, attached at the side of the
prism casing.

For fuller particulars regarding its construction see the directions accom-
panying the instrument.

Nos. 191 and 191". *ENGELMANN'S Micro-spectro-photometer. This

apparatus • - designed for quantitative micro-spectrum analysis - is con-
structed on the principle of VIERORDT'S spectro-photometers. The Apparatus
No. 191 is provided with prisms, No. 191" with grating for the production of the
spectrum.

As to the use of the apparatus we would refer to the instructions given in
Zeitschr. f. wiss. Mikrosk., vol. V, 1888, pp. 289—296 and Sitzungsber. d. Berl.
Akad., vol. XXXII, 1902, pp. 706—710.

No. 192. *Drum fitted with PORRO'S Prisms for erecting the images.

Similarly as in our image erecting microscopes the PORRO prisms of this ocular
are encased in a drum, below which is a sleeve fitting the tube of the microscope.
A second sleeve on the upper end of the drum takes any ocular desired.

No. 193. AMICI Erecting Prism • ("prismc redresseur"). This prism,

which is supplied in a mount fitting the ocular, besides erecting the image affords
the additional advantage of a comfortable position of the head, the optical axis
(the direction of vision) being inclined about 30° to the axis of the tube.

Nos. 194 and 195. *lndex-Oculars. In the course of class demonstrations
it is often found desirable to be able to mark any particular point of the object
by means of an index. To meet this want we supply the HUYGENIAN oculars 2
and 3, as also compensating ocular 6 - - in the form of drum oculars with micro-
meter (see' p. 76) - fitted with a movable index, No. 195", which can be
adjusted laterally by means of a screw in the same manner as a micrometer scale.

No.

Marks

Codeword

191

EXGELMAXN's Micro-spectro-photometer, in case ....

480.-

Pepiuo

191»

The same apparatus as No. 191, but with prating . . .

510.-

Pepite

192

Drum fitted with PORRO's Prisms without Ocular,

in case

40.-

Pepitoso

193

AMICl's Erecting Prism, in case

25.—

Peragrar

194

Index Ocular HUYGENIAN Ocular 2 or 3

86-

Peraleda

195

Index Ocular Compensating Ocular 6

49.-

Pcranton

195"

Index, alone

j

Percance

Cross-line Oculars. The process of centring the object-stage or the ob-
jective by means of special centring appliances as well as in investigations in
polarised light requires that the centre of the field should be indicated by a mark
in the plane of the diaphragm of the ocular. For this purpose we supply glass
discs ruled with cross-lines for dropping into the ocular.

The addition of such a disc raises the price of an ocular by Marks 4. — .
If it be also desired to have the eye-lens adjustable, a further charge of Marks 7. —
is to be added.

In subsequent ordering of the glass disc ruled with cross-lines it should
be stated whether the discs are intended for ordinary oculars or oculars with
adjustable eye-lens.

's Prism and Capillary Rotators.

These two instruments are more especially designed to facilitate the examin-
ation, from different sides in succession, of objects so small that the control of their
movements under the microscope would be difficult to accomplish by hand.

Nos. 196 and 107. Prism Rotator. Fig. 43. The upper surface of the
object is seen direct, the lower side is viewed after double reflection (see Fig. 43b)
at Si and s->, while rotation round the axis aa and reflection at A's facilitate
examination of all remaining portions of the object.

a (% Full Size).

Fig. 43. Prism Rotator, >To. 196.

b (magnified X 2)-

Sectional diagram

of prisms .

(xREENOUGH's Prism Rotator, in case

The same apparatus as No. 196, but with double reflection
for side views, in case

Marks Codeword
62. — Perceptor

75. — Pereudlr

= go —

The positions "right" and "left" being reversed in consequence of the single
reflection at 83, and as this would cause inconvenience in certain cases we construct a
second form of the instrument, Xo. 11)7, in which the objectionable
reversal is obviated by the addition of another prism.

No. 198. The Capillary Rotator, Fig. 44, serves to rotate about a hori-
zontal axis small objects which may be contained in a capillary tube. The in-
strument is so arranged that the capillary tubes may be rotated within a chamber
fitted with cedar-wood oil, so as to obviate the disturbing effects of irregular
refraction and of reflection caused by the walls of the tubes.

. 44. Capillary Rotator. No. 198. (:'/6 Full Size.)

While the Prism Rotator is primarily designed for use on Binocular Stand Xa.
but may also be used with other stands having a stage opening )>;> mm (l'/3 in.)
in diameter, the Capillary Rotator, because it may be held by means of clips like
any ordinary object-carrier, is adapted for all stands alike.

Regarding the details of the construction of the two instruments see Zeit-
schrift f. wiss. Mikrosk., vol. XIV, 1897, pp. 304 — 312.

flrtificial Illuminating appliances for the Microscope.

Lamplight, if properly regulated, may almost completely replace good
daylight.

It is advisable to interpose between the source of light and the mirror of
the microscope a spherical glass flask filled with water (such as is sometimes
used by engravers) or, better still, a simple collective lens, so as to project a
sufficiently large image of the source of light upon the iris-opening or upon
the mirror.

No.
198

GREENOUGH's Capillary Rotator

Marks Codeivord
50. — Pcrdcras

No. UW. Incandescent Gas Lamp and Glass Flask. For the purpose
of illumination we supply an incandescent glass lamp mounted on a brass
stand with ordinary burner and Jena glass chimney together with two reserve
mantles and in combination with this lamp a glass flask on a special stand.

Xo. 200. Glass Flask on Stand. This flask is also supplied separately.
It has a diameter of about 15 cm (6 in.). It is most efficient when placed midway
between lamp and microscope at a distance of 15 cm from both.

Xo. 201. Collective Lens with Iris-diaphragm. This apparatus consists
of a simple collective lens (of about 125 mm [47/g in.] length) with an iris-
diaphragm attached to its mount. It stands upon a massive foot and the lens
is adjustable in height. This appliance helps, not only to produce a better image
of the source of light, but also to confine the illuminated portion of the field
within sharply defined limits. It is for this reason that it is so well adapted for
illumination by means of the vertical illuminator (see pp. 34 and 35).

Spectroscopes.

Nos. 202 to 204. BROWNING'S Hand-Spectroscopes.

This form of spectroscope is fitted with a set of AMICI prisms of great
dispersion and is principally intended for the examination of large objects as,
for instance, troughs filled with liquid matter.

For particulars of other spectroscopes consult the special prospectuses
issued by our Department of Optical Measuring Instruments.

No.

Marks

Codeword

1 '.»'.»

Incandescent Gas Lamp with Glass Flask on Stand . .

22.—

PerdidtiM)

200

Glass Flask separately

7.—

Perdigon

201

Collective Lens with Iris-diaphragin, on stand with massive

round foot

30.—

Perdon

202

Hand-Spectroscope, without comparison prism, in case

40.-

Perdurar

203

with „ „ „ „

46.-

Peregrina

201

„ ., with scale of wave lengths „ „

80.-

Perenal

Qail

Heating apparatus.

Nos. 209 to 211. L. PFEIFFER'S Heating Chamber for heating micro-
scopical objects during observation. (See L. PFEIFFER, "Protozoan als Krankheits-
erreger etc", 2nd edition, Jena, 1891.)

The chamber consists of a mahogany box encasing the whole of the micro-
scope, with a window in the front to admit the necessary light. On either side
is a closely fitting door through which the specimen can be moved with the
fingers. The side walls may also be completely folded back, carrying with them
the halves of the back wall, which is divided down the middle.

The whole (chamber and microscope stand) rests upon a thick metal plate
on three legs. The metal plate is heated from below by a micro-burner, No. 212,
controlled by a thermo-regttlator, No. 215, and should be adjusted so as to burn
with smokeless flame.

By this means the whole stand and the air surrounding it are gradually
brought to the same temperature, so that after a reasonable lapse of time the
readings of the thermometer placed in the air space indicate the actual tempera-
ture of the object on the stage.

The temperature may be raised to 45° C (u? F) without risk of injury
to the Stand or optical equipment.

We supply this heating chamber in various forms, suitable for Stands with
the older form of fine adjustment and for those with BERGER'S micrometer
movement.

In subsequent orders the factory number of the Stand, intend-
ed to be used with the heating chamber, should be given. A tJiermo-
regulator, No. 215, as well as a thermometer, accompanies each
heating chamber, but the micro-burner, JVb. 212, must be ordered
specially.

Nos. 213 and 214. L. PFEIFFER'S Heating Stage. We are prepared to
supply this apparatus as constructed by E. LEYBOLD'S successor, of Cologne.

No.

•wo

PFEIFFER'S Heating Chamber for Stand IV

Marks Codeivord
70 — Pergenaba

210
211
212
213

„ 1 and III ....
„ V
Micro-burner for the Heating Chamber
Heating Stage with flat surface .

100.— Periclylus
65. — Perifcrme
4.50 Periliistre
9. — Perineo

214

3 concavities .... ....

15 — Periodo

215

Thermo-regulator for above heating appliances ....

10.— Periplo

— 93 —

This stage consists of a glass box made by the LEYBOLD sealing process, which
may be directly used as an object-carrier. A thermometer and inlet and outlet
tubes for heated water are fitted at the side of the glass box. In order that
this stage may also be available for hanging-drop observations, we supply the
same, if so ordered, with three concavities, ground out of the upper glass surface,
upon which the cover-glasses are placed.

No. 216. ZOTH'S Cooling Trough, which is more especially designed
for purposes of micro-projection, may also be fitted with a thermometer and
will in this form be found to serve as a useful heating stage.

Other accessory flpplianees.

Xo. 217. MALTWOOD'S Finder. This simple contrivance for re-finding
certain points of an object consists principally of a net-work of separately num-
bered small squares photographed upon glass. (See Zeitschr. f. wiss. Mikrosk.
vol. V, 1888, p. 40.)

No. 218. BORN and PETER'S Orientation Plate, constructed by us at

the suggestion of the gentlemen after whom it is named, serves to mark the
position of objects contained in hardening paraffin and at the same time to
impress the lines of direction upon the paraffin blocks. For the latter purpose
one side of the plate has several parallel grooves, of equal width and with sharp
edges, cut into it. (See Zeitschr. f. wiss. Mikrosk., vol. XV, 1898, pp. 31 — 49.)

We generally supply a pair of glass set-squares, No. 219, together with the
instrument.

No. 220. Turn-Table (Tournette), on wood base, for ringing specimens.

No.
216

ZOTH'S Cooling Trough, with thermometer

Marks

17.50

Codeword
Peritoneo

217

MALTWOOD's Finder, in case

20 —

Perlado

218
21'-)

BORN and PETER'S Orientation Plate, with glass set-squares
Pair of glass set-squares separately

40.-
10.—

Perlongar
Permeable

220

Turntable (Tournette) on wooden base

11.—

Permitir

, Sena.

94

Bell-Glasses, Slides, Cover-Glasses.

Bell-glasses for covering up microscopes (dust-
proof), incl. a stout cloth-covered mill-board base:

Large size, about 38 cm (15 in.) high, 24 cm (9V2 in.)
inside diameter

Smaller size, about 35 cm (14 in.) high, 20cm (8 in.)
inside diameter

Plane Ground-glass Discs for use as bed-plates:

for the large bell-glasses

for the smaller bell-glasses

Slides of the Giessen size, 48 X 28 mm (!7/8 X iy8 in):

a) white crown-glass, unground edges, per 100 ....

b) white crown-glass, ground edges, per 100 .....

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

Slides of the English size, 76 mm X 26 mm (3 X 1 in.) :

a) white crown-glass, unground edges, per 100 ....

b) white crown-glass, ground edges, per 1 00 ....

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

Slides of extra large size, 87 mm X 37 mm' (33/8 X I1/* in.):

a) white crown-glass, unground edges, per 100 ....

b) white crown-glass, ground edges, per 100 ....

Slides with polished concavities:

a) small size, 55 mm X 32 mm (2J/4 X l'/4 in-)> best make and
finish, edges bevelled, each

b) extra large size, 87 mm X 37 mm (33/8 X 1V2 in.), best
make, edges bevelled and polished, each

Slides with cemented glass rings, for moist chambers,
1 or 2 mm deep, each

Cover-glasses, Squares :

a) size: 24 mm D, per 100

b) „ 21 „„ ,,100

c) „ 18 „ „ „ 100 .

d) „ 15 „ „ „ 100

e) „ 12 „ „ „ 100 . ,

Marks < 'oil,

10.

1.50
2.50
5.—

8-
8.-

7.-

Pernendor

N. Perneria

7. — Periii iron
3.30 Pernwlar

Perolillo
Pcrpasar
Perpetrar

Perplejo

Per(|iierir

Perrezno

•'{.30 Persei|iiir
5. — Persiiriiar

0.30 Persona/a

1.— Person ilia

O.SO IVrsnmlir

4.30 PersiiaMir

3. — Pertinaee

2. — Pt'rtnrltnr

1.50 Pernlera

1 . — Perverse

95

No.
•231

Cover-glasses. Circles:

a) size : 24 mm diameter.

per 100 . . .

Marks ( 'odtword
5 Pesadllla

b) „ 21 „

., 100

Pi'salicor

c) ., 18 „

,,100

"* .">0 Posaroso

d) ,. 15 .,

e) ,. 12 ..

.,100
..100

2. — Pescadora
1 ."lit Pescozon

Stt

Cover-glasses. (M)loiiss:

a) si/.e : 32 mm X 24 mm,

per 100

6 — Pcsebre

b) "1 X 21

,,100

'•> ~>0 ]Y^]HI lit ;ll

The thickness of the above cover-glasses varies between 0.15 mm and 0.22 mm ;
one third must be added to the prices quoted if covers of special given
thickness are required.

With regard to systems for dissecting, magnifiers, dissecting stands
and stands for magnifiers please consult our special prospectus relating
to these pieces of apparatus.

In order to meet the requirements of our customers abroad we shall at all
times be pleased to obtain from the best sources, and supply at maker's prices.

Microtomes.

Cases of Dissecting Instruments,

Microscopic Preparations

which may be required to supplement any microscopic outfit purchased from us.

ciJJ, Skua.

96 =

XA VHUNGEK.JENA -

Fi£. 45.
Stand III housed in its cabinet.

('/., Full Size.)

167.

97

Complete Microscopes.

As a convenient guide to the selection of stands and their optical equipment,
together with the requisite accessory apparatus, we append a number of com-
binations suitable for a great variety of purposes. It is not, however, our inten-
tion to place the least restriction on the free choice of our customers.

In ordering a set corresponding to one of the specifications it will be
sufficient to quote either the respective number and the total cost or the
codeword.

A. Complete Microscope Outfits, comprising all the more important
Accessory Apparatus.

Specification 1.
Apochromatic Objectives:

1 6 mm 8 mm 4 mm

0.30 num. Ap. 0.65 num. Ap. 0.95 num. Ap.

80.— 100.— 140. — . Mk. 320. —

2.5 mm (Water Immersion) „ 250. —

1.25 num. Ap.

2 mm 3 mm (Homog. Immers.)

1.30 num. Ap. 1.40 num. Ap.

300.— 400.— , 700.—

•
Compensating Oculars :

24 8 12 18

2O. — 20. — 30. — 30. — 25. — „ 125. -

6 (Micrometer Ocular, No. 122) ,, 31. —

Achromatic Objectives:

ao a2 a* aa B

12. — 12. — 40. — 27. — 30. — „ 121. —

PI -D* (Water Immersions)

20.— 75.— „ 95.—

HUYGENIAN Oculars:

i, 4. 5 , 18.—

2 with cross lines and adjustable eye-lens ... „ 17. —

3 (Micrometer Ocular, No. 120) „ 18. —

Mk. 1695. —

Glass Cell for the Plankton-searcher No. 2030 . ,, 3.50

Centring Achromatic Condenser No. 29 .. „ 75.—

ENGELMANN'S Micro-spectral Objective No. 34 „ 160.—

Revolving Vulcanite Stage No. 45 „ 25. —

263.50

Carried Forward Mk. 1958.50

ef O" • ct

a.zv >bci:o, cTcna,

= 98

Brought Forward Mk. 1958.50

Revolving Nose-piece for 4 Objectives, No. 50 Mk. 25.—

Tube-slide No. 52 „ 8.—

6 Objective slides No. 53 „ 48.—

Case to hold 6 Objective-slides, No. 55 .... „ 15. —

Drawing Apparatus No. m ,, 60. —

Drawing-table No. 114 , „ 52. —

Stage Micrometer No. 118 10.—

Screw Micrometer Ocular No. 125 „ 105. —

Stage Screw Micrometer No. 126 „ 120. —

Cover-glass Gauge No. 129 „ 30. —

Rules on plate-glass No. 132 and 134 ... „ n. —

Fully divided Circle No. 139 „ 20.—

Haemocytometer No. 149 30. —

Apertometer No. 156 „ 90. —

Test-plate No. 157 „ 10.—

Diffraction Apparatus No. 158 „ 20.—

Polarising Apparatus No. 169 ,, 58. —

Assortment of Selenite and Mica Films, No. 179 „ 15. —

Spectroscopic Ocular No. 190 „ 200. —

Drum fitted with PoRRO-prisms, No. 192 .... „ 40. —

Index Ocular No. 195 49-—

Prism Rotator No. 197 75. —

Capillary Rotator No. 198 „ 50. —

Gas Lamp and spherical glass flask, No. 199 . . ,, 22. —

Collective Lens with iris-diaphragm, No. 201 . .. 36. —

Heating Stage No. 214 , 15.—

Thermo-regulator No. 215 „ 10. —

MALTWOOU'S Finder No. 217 „ 20. —

BORN-PETER'S Orientation Plate No. 218 . . „ 40. —

Turn-table No. 220 „ n. —

Outfit completed by adding:

a) Stand IB No. 5710 , 425.-

Leather travelling case „ 36.—

Packing ,, 9. —

or

b) Stand I E No. 6010 , 440.-

Leather travelling case „ 36. —

Packing ,, 9. —

Codeivord

1295.—

470— Mk. 3723.50 Pestiferer

485.— Mk. 3738.50 Pestonaiido

Regarding apparatus for dissecting purposes required as a suitable complement to Specification I
see the foot note on p. 99.

Specification 2.
Achromatic Objectives :

a2 a* aa AA B C DD

12. — 40. — 27. — 30. — 30. — 30. — 50. — Mk. 219 —
E with corr. collar. F with corr. collar.

80.— 95.— „ 175.—

Carried Forward Mk. 394. —

= 99 ==

Brought Forward Mk. 394. — Codeword

PI D* J with corr. collar (Water Immers.)
20. — 75. — 130. — Mk. 225. —

I "

— (Homogeneous Immersion) „ 125. —

HUYGENIAN Oculars :

i, 2. 4- 5 ,. 24-—

3 (Micrometer Ocular No. 120) „ 18. —

,, /oo. —

Glass Cell for the Plankton-searcher No. 2030 . „ 3.50

Revolving Vulcanite Stage No. 45 „ 25.—

Revolving Nose-piece for 4 Objectives, No. 50 „ 25. —

Drawing Apparatus No. in , 60.—

Drawing-table No. 114 „ 52. —

Stage Micrometer No. 118 „ 10. —

Screw Micrometer Ocular No. 124 .... „ 90. —

Cover-glass Gauge No. 130 „ 15. —

Haemocytometer No. 149 „ 30. —

Apertometer Xo. 155 . . . . . 70.—

Test-plate No. 157 „ 10.—

Polarising Apparatus No. 169 58.—

Selenite Film for Red of the I. Order, No. 180 „ 3.—

Spectroscopic Ocular No. 190 „ 200. —

Drum fitted with PoRRO-prisms, No. 192 ... „ 40.—

Index Ocular No. 194 „ 36.—

Prism Rotator No. 196 „ 62.—

Capillary Rotator No. 198 , 50.—

Gas Lamp and spherical glass flask, No. 199 .. „ 22. —

MALTXVOOD'S Finder No. 217 „ 20.—

Outfit completed by adding: „ 881.50

a) Stand I B No. 5705 ,, 400.—

Leather case „ 36. —

-^ „ 444.— Mk. 2111.60 Petardant
or

b) Stand IE No. 6005 „ 415 —

Leather case „ 36.—

Packing „ 8— 459_ -2126.50 Petechial

or

c) Stand HIE No. 6505 , 365.—

Packing_^ *— „ 373— „ 2040.60 Petiginis

or

d) Stand IV E No. 7205 335-—

Packing-^ !Lz „ 343.- „ 2010.50 Petilleres

As a suitable complement to specifications I and 2 for dissecting purposes we would recommend
the addition of one of the Specifications Nos. 17, 18, 20 or 21. If No. I7a be chosen, the Prism Rotator
and the Capillary Rotator, and in the Nos. 20 and 21 the Objective a* as well as the HUYGENIAN Oculars
2 and 4, would be omitted.

Oatl

IOO

B. Complete Microscopes, equipped with only the most indispensable

Accessory Apparatus, but generally sufficient for histological, bacteriological,

botanical and zoological research.

Specification ,'i.

Apochromatic Objectives :

16 ram 8 mm

4 mm

0.30 num. Ap. 0.65 num. Ap. 0.95 num. Ap.
80. — 100. — 140. — . .

2 mm (Homogeneous Immersion) . .

1.30 num. Ap.

Mk. 320. —
„ 300. —

Codeword

155 —

Compensating Oculars:

2 4 8 12

2O. — 20. — 30. — 30. — „ IOO. —

6 (Micrometer Ocular No. 122) • . „ 31. — -.,,

,-VIK. 75 *• —

Tube-slide No. 52 8.—

4 Objective-slides No. 53 „ 32.—

Case to hold 6 Objective-slides, No. 55 „ 15. —

Drawing Apparatus No. 1 1 1 „ 60. —

Stage Micrometer No. 118 „ 10. —

Haemocytometer No. 149 • „ 30. —

Outfit completed by adding:

a) Stand IB No 5705 „ 400. —

Polarising Apparatus No. 169, and

Selenite Film No. 180 „ 61.—

Packing ,, 4. —

or

b) Stand HIE No. 6505 365.—

Polarising Apparatus No. 169. and

Selenite Film No. 180 , 61.—

Packing ,, 4. —

or

c) Stand HID No. 6405 290.—

Polarising Apparatus No. 169, and

Selenite Film No. 180 „ 61.—

Packing „ 4. —

or

d) Stand IV D No. 7105 „ 260.—

Packing „ 4. —

465.— Mk. 1371.— Petitorias

430.— „ 1336.— IVtriliaiit

355-— ,, 1261.— Petrolerie

264.— „ 1170.— Pfiimlanin

IOI

Specification 4.
Achromatic Objectives:

a2 a* AA C DD F

12.— 40.— 30.— 30.— 50.— 75.— . . . Mk. 237.—

Codeword

PI D* J (Water Immersions)

20.— 75.— no.— „ 205.—

I "

(Homogeneous Immersion) „ 125. —

HUYGENIAN Oculars :

i. 2. 4. 5 . . . „ 24.—

3 (Micrometer Ocular No. 120) „ 18. — »,, -• _

Glass Cell for the Plankton-searcher No. 2030 . „ 3.50

Revolving Nose-piece for 4 Objectives, No. 50 „ 25. —

Drawing Apparatus No. in „ 60.—

Stage Micrometer No. 118 „ 10. —

Counting Chamber No. 142 „ 15. — n-ieo

Outfit completed by adding:

a) Stand IA No. 5605 ,, 325.—

Polarising Apparatus No. 170, and

Selenite Film No. 180 „ 44._

Packing^ 3jl .. 372-- Mk. 1094.60 Piariegas

or *

b) Stand HID No. 6405 „ 290.—

Polarising Apparatus No. 170, and

Selenite Film No. 180 „ 44.

Packing __„ 3.- ^ 33;,_ 1059.60 Picadinha

or

c) Stand IV D No. 7105 „ 260.—

Polarising Apparatus No. 170, and

Selenite Film No. 180 „ 44.—

Packing » 1— „ 307— ,, 1029.50 Picamare

or

d) Stand IIIC No. 6305 250.—

PackinS_^ 1^ „ 253._ „ 975.60 Piearaza

or

e) Stand IV C No. 7005 „ 225.—

Packmg — 1; ^H „ 228.— „ 950.50 Picaresque

or

f) Stand IV B No. 6905 „ 210.—

Packing_,, 3.- 2I_

Qazt

-^i
f Or THf

I UNIVERSITY 1
\ or J

X. f>.. ...V S

IO2

C. Microscopes suitable for specific purposes.

Specification 5.
Microscopes for bacteriological research.

(A suitable outfit for clinical laboratories, hospitals, hygienic institutions, medical practitioners

and veterinary surgeons.)

Achromatic Objectives :
AA DD

30. — 50. — Mk. 80. — Codeword

Apochromatic homogeneous immersion
Objective:

2 mm „ 300. —

1.30 num. Ap.

HUYGENIAN Oculars:

2, 4 " I2-—

Compensating Oculars:

4 8

20.— 30.— „ 50.—

6 (Micrometer Ocular No. 122) „ 31.—

Revolving Nose-piece for 3 Objectives, No. 49 „ 20.— Mk ..

Outfit completed by adding:

a) Stand IA No. 5610 „ 35°-—

Leather travelling case „ 36.—

Packing .. 3-— „ 389.— Mk. 882.— Pichorra

or

b) Stand HID No. 6410 „ 3'5-—

Packing „ 3.— 318.— „ 811.— Picicorne

or

c) Stand IV D No. 7105 „ 260.—

Packing „ 3.— 263.— 756.— Piconero

Specification 6.
Microscopes for similar purposes, but less expensive.

Achromatic Objectives:
A DD

20. — 50. — Mk. 70. —

i "
— (Homogeneous Immersion) „ 125. —

HUYGENIAN Oculars :

2, 4 I2—

3 (Micrometer Ocular No. 120) „ 18. —

Revolving Nose-piece for 3 Objectives, No. 49 20.— Mk 2^ —

Carried Forward Mk. 245. —

103

Brought Forward Mk. 245. —
Outfit completed by adding:

a) Stand III D No. 6405 Mk. 290.—

Packing „ 2.50

Codeword

„ 292.50 Mk. 537.50 Picoteares

b) Stand IV D No. 7 105

Packing_^

.. 262.50 „ 607.50 Picramyle

c) Stand IV C No. 7005 ........ „ 225. —

Packing „ 2.50 22 47250 picrosnlilie

d) Stand VI» No. 82

f) Stand VB No. 7505

„ 152— „ 397.- Pictores

e) Stand VI« No. 83 (Travelling Microscope) „ 165.—

Packing „ 1.50

„ 166.50 „ 411.50 Pieudos

. . . . „ 1 20. —
Packing „ 1.50

„ 121.50 „ 366.50 Piecard

The optical details enumerated in Specifications 5 and 6 were adopted for the Microscopes used in
the Prussian Military Hospitals. Professor R. KOCH declares them to be indispensable in
bacteriological research.

The total cost of Specification 6 may be still further reduced by omitting the micrometer
Ocular No. 120 and by substituting Objective D for DD, which would result in a saving of
Mk. 33 — .

Specification 7.
Microscopes for histological, botanical and zoological investigations,

Achromatic Objectives:

a2 a* A C E

12. — 40. — 2O. — 30. — 6O. — ....

PI (Water Immersion)

— - (Homogeneous Immersion)

HUYGENIAN Oculars:

Mk. 162.—

„ 20. —

„ 125.—

2, 4

3 (Micrometer Ocular No. 120)

12. —

18.—

Mk. 337.—

Glass Cell for the Plankton-searcher, No. 2030 . „ 3.50

Revolving Nose-piece for 3 Objectives, No. 49 „ 20. —

Drawing Apparatus No. in „ 60. —

Stage Micrometer No. 118 „ 10. —

93-5°

Carried Forward Mk. 430.50

{»», Stna.

IO4

Outfit completed by adding: Brought Forward Mk. 430.50 Codeword

a) Stand HID No. 6410 ........ Mk. 3'5-—

Packing „ 3.— ^ 3lg_ Mk_ 74850 pienotto

b) Stand IV D No. 7105 ........ „ 260.—

Packing ,. 3-— „ 2&3._ n 693.50 Piepente

c) Stand IV C No. 7005 ........ „ 225.—

Packing „ 3.- 22g_ 668.50 Pietrisco

d) Stand VI» NO. 82

. . . . „ 15°-—
Packing „ 2.—

^ 53.2.50 pjeTaIlato

e) Stand VB No. 7505

„ 120.—
Packing „ 1.50 I2I-50 _ 552 _

Specification 8.
Microscopes for similar purposes, but less expensive.

Achromatic Objectives:
.02 A C E

12. — 2O. — 30. — 60. — Mk. 122. —

- (Homogeneous Immersion)

HUYGENIAN Oculars :

2, 4

3 (Micrometer Ocular No. 120)

„ 125.—

12. —

i8.—

Revolving Nose-piece for 3 Objectives, No. 49 „ 20.—

Drawing-prism No. 109 „ 21.—

Drawing-board No. 115 „ 2.50

Stage Micrometer No. 118 . 10. —

Mk. 277.-

.. 53-50

Outfit completed by adding:
a) Stand III D No. 6405

b) Stand IV D No. 7105

c) Stand IV C No. 7005

d) Stand VI » No. 82

.... „ 290. —

Packing - I— „ 293.- Mk. 623.50 Pij?neratio

.... „ 260. —

Packing 3-- 26j_ 593.50 pj-rnorada

„ 225.—
Packing „ 3.-

Pi(rralltes

15°-—

Packing 2.50

e) Stand VB No. 7505

Packing „ 2.- I22_ 45250

105

Specification 9.
Mii-1-oni-ii/H'H <i<lap1etl for histological. botanical and zoological courses;

also in accordance -.i'ith the German regulations for the conduct of pharmacies.

Achromatic Objectives: Codeword

a2 A D

12. — 20. — 35. — Mk. 67.—

HUYGENIAN Oculars :

2, 4 „ 12. —

Ocular Micrometer No. 117 ,

Outfit completed by a'dding:
a) Stand VI » No. 80 . .

. . • 5-—

. . . . „ 130.—
Packing „ 1.50

Mk. 84.—

•31-50 Mk. 215.60 Pilavistis

b) Stand VA No. 7405 „ 100. —

Packing „ I. —
or (if Polarising Apparatus be desired)

c) Stand VD No. 7705, with Iris-diaphragm

No. 3810 178.—

Packing „ " 1.80

-- „ 186.— Pileaiitlie

.. 179.80 „ 263.80 Filierepos

Specification 1O.
Microscope* adapted for Mstological investigation in polarised light.

Achromatic Objectives:
a2 A DD

12. — 2O. — 50. —

— (Homogeneous Immersion)
HUYGENIAN Oculars:

2, 4

3 (Micrometer Ocular No. 120)

Mk. 82.—

„ 125.—

12. —

18.—

b) Stand IV F No. 7305

d) Stand VD No. 7705, with Iris-diaphragm
No. 3810 ..............

Mk. 237. —

Outfit completed by adding:

a) Stand HID No. 6410 „ 315.—

Polarising Apparatus No. 170, and

Selenite Film No. 180 , 44.—

Packing „ 2.50

„ 361.50 Mk. 698.50 Pillobolo

295—

Packing „

.. 297.50 „ 534.50 Pillottava

c) Stand IVD No. 7105 „ 260.—

Polarising Apparatus No. 170, and
Selenite Film No. 180 „ 44.—

Packing 2.?o

„ 306.50

543.50 Pilosorum

Ll£ 179.50 416.50 Pilotrico

= io6 =

Specification 11.
Microscopes adapted for mineralogical and crystallographic investigations.

Achromatic Objectives:
a2 A DD F

12.— 20.— 50.— 75. — Mk. 157. — Codeword

i"

— (Homogeneous Immersion) „ 125. —

HUYGENIAN Oculars with cross-lines :

i, 2, 4 „ 3°-—

3 (Micrometer Ocular No. 120) „ 18. — j^

Tube-slide No. 52 8.—

5 Objective-slides No. 53 „ 40.—

Case for 6 Objective-slides No. 55 „ 15. —

Drawing Apparatus No. in „ 60.—

Stage Micrometer No. 118 „ 10.—

Adjustable Iris-diaphragm with Ocular No. 178 „ 25.— 158.—

Outfit completed by adding:

a) Stand HI ME No. 6710 „ 600.—

Goniometer Ocular No. 127 (without

divided circle) „ 20. —

Packing ., 4.— ^ 624_ Mk 1112_ pjpabimus
or

b) Stand HIMD No. 6605 „ 5°°-—

Goniometer Ocular No. 127 (without

divided circle) „ 20. —

'2 Iz: „ 524.— 1012— Pipaverunt

Specification 12.
Microscbpes for mineralogical and crystallographic courses.

Achromatic Objectives:
A D

20.— 35.— Mk. 55.—

HUYGENIAN Oculars with cross-lines:

2' 4 __n 20-— Mk. 75.—

Outfit completed by adding:

a) Stand IV F No. 7305 „ 295.—

Packing ^ ii£ .. 297.50 Mk. 372.50 Pirofobia

or

b) Stand VD No. 7705 „ 170.—

Packing „ 1.50 ,7, 5Q 246.50 Piropeaba

= 107 =

Specification 1,'i.
Microscopes specially (ttfajitctl for chemical laboratories, for paper and celluloid

factories, for breweries and dairies.
Achromatic Objectives:

a2 A D
12.— 20.— 35.— Mk. 67.— Codeword

i"
— (Homogeneous Immersion) „ 125

HUYGENIAN Oculars:

2, 4 , 12.—

3 (Micrometer Ocular No. 120) . . . 18. —

Mk. 222. —

Revolving Nose-piece for 3 Objectives, No. 49 „ 20. —
Stage Micrometer No. 118 „ 10. —

Counting-chamber No. 142 „ 15. —

)> 45' —

Outfit completed by adding:

a) Stand HIE No. 6505 365.—

Polarising Apparatus No. 170, and

Selenite Film No. 180 „ 44.—

Packing „ 2.50 ^ 4ii5Q Mk 6786() piruetano

or

b) Stand IV F No. 7305 „ 295.—

Packing^, 2.50 ^

or

c) Stand VD No. 7705 with Iris-diaphragm

No. 3810 „ 178. —

Packing^, ijg

Specification 14.

Microscopes for similar purposes, but somewhat cheaper.
Achromatic Objectives:
ACE

20.— 30. — 60.— ............ Mk. no.—

HUVGENIAN Oculars:

2- 4 ................... „ 12.—

3 (Micrometer Ocular No. 120) ..... 1 8. — ,.

- 1- - Mk. 140. —

Revolving Nose-piece for 3 Objectives, No. 49 „ 20.—
Counting-chamber No. 142 ......... „ 15. —

Outfit completed by adding:!

a) Stand IV F No. 7305 ........ „ 295.—

Packing — „ - !Jg „ 297.5o Mk. 472.60 Piscipules
or

b) Stand VD No. 7705, with Iris-diaphragm

No. 3810 ............. „ 178. —

_ LJg „ 179.50 „ 354.50 Plsonibus

or

c) Stand VB No. 7505 ........ „ 120.—

,21.50 296.50 Pistabunt

ciss, 3iii a.

= io8

Specification 15.
Specially suitable for customs examinations of textile goods, etc.

Achromatic Objectives:
a2 A D

12.— 20.— 35.— Mk. 67.— Codeword

HUYGENIAN Oculars:

2, 4 „ 12

3 (Micrometer Ocular No. 1201 . . . 18. — ,

Z Mk. 97 . —

Outfit completed by adding:

a) Stand VD No. 7705, with Iris-diaphragm

No. 3810 , 178.—

Packing_,, Li: ,. I79._. Mk. 276.- Pistazite

or

b) Stand VA No. 7405 „ 100. —

Packing „ i. — „„

Specification 16.
For the examination of opaque objects, metal specimens, etc.

Achromatic Objectives:
a2 A C

12.— 20.— 30.— Mk. 62.—

HUYGENIAN Oculars:

' ' '2 I2'~ Mk. 74.—

Vertical Illuminator No. 42 „ 18.—

Collective Lens with Iris-diaphragm, No. 201 . „ 36. —

» 54- —

Outfit completed by adding:

a) Stand VA No. 7405 „ 100. —

Packing — „ IJJQ „ I0r.5o Mk. 229.50 Plaudebat

or

b) Stand IX No. 91 „ 50.—

51.50

179.60 Plausitavi

The apparatus designed by MARTENS and HEYN for the investigation and micro-photography of
metal specimens fulfils the higher demands of the subject. See our special Prospectus (M. 59) relating
to this apparatus.

log

D. Specifications for Binocular and Monocular image-erecting Microscopes.

Specification 17.
Binocular Microscopes.

Paired Objectives:

Codeword

45— 45— 45-— 45— 55— ..... Mk. 235.—
Paired Oculars:

2- 3, 4 ................. „ 3°—

Glass Cell for Plankton-searcher No. 2030 . j.co >

! Mk. 274.50

Outfit completed by adding:

a) Stand Xa No. 95 .......... „ 195. _

Prism Rotator No. 197 ...... „ 75.—

Capillary Rotator No. 198 ..... „ 50. —

^>ng — „ - 3^: n 323-_ Mk. 59750 piufativos

or

b) Stand Xb No. 96 ......... „ 260.—

Dissecting Stand No. 9605 .... „ 467—

Packing^: _ lig „ 304-50 „ 579.- Plusculos

•

Specification 18.

Binocular Microscopes, somewhat cheaper.
Paired Objectives:

(W) (W)

45— 45— ............... Mk. 90.—

Paired Oculars:

2' 4 ' ' •• 24— Mk. ri4.-

Outfit completed by adding:

a) Stand Xa No. 95 .......... „ 195.—

ang — - -- ^ ., I97-50 Mk. 311.60 Podasimus
or

b) Stand Xb No. 96 .......... „ 26o.—

Packing ^. —

^ — - - £— „ 263.— „ 377.— Podlsmavit

=^=^= I IO ==

Specification 19.
Corneal Microscopes (see p. 65.)
Paired Objectives:

(55) (ao)

45.— 45. — Mk. go. — Codeword

Paired Oculars:

2> 4 • • • • " 24'~ Mk. 114.-

Outfit completed by adding:

a) Stand X<- No. 98 . „ 220.—

Packing „ 3.50 ^ 2235Q i]k m-M Podredura
or

b) Stand X« No. 9810 „ 250.—

Sole-plate with Chin-rest, No. 9820 . „ 45. —

Packing ., 5.- ^ 30Q _ ^ 4U_ poetabo,.

Specification 2O.

Monocular, image-erecting Microscopes specially adapted for

dissecting.

Stand XI No. 9905 '. Mk. 140.—

Outfit completed by adding:

a) Achromatic Objectives:

55 mm aj a* A C

15. — 12. — 40. — 20. — 30. — . . Mk. 117. —

HTJYGENIAN Oculars:

2' 4 _i i^= „ 129-

Revolving Nose-piece for 3 Objectives,

No. 49 „ 20. —

Packing „ 2.— 22 _ Mk 291_ poetassimo

or

b) Achromatic Objectives:

3o (in spec, mount) 83

12.— 12.— „ 24. —

HUYGENIAN Oculars:

2, 4 ' I2-—

Packing '-5° 37.5o „ 117.60 Poctoivsti

Specification 21.

Combined new Drawing Apparatus for low magnifications
and Dissecting Stand for large objects.

Stand P II No. 103 (see details on p. 67) ... Mk. 410.—

Packing .. 5.50 Mk 41550 palicoj0

Index.

Page

Achromatic objectives .... 20 — 23

Adjustment, Means of .... 40—42

Analyser oculars 84

Analysers 84

Apertometer 81 — 82

Aperture, numerical 11 — 12

Apochromatic objectives . . . 12 — 15

d". for 10 inch tube .... 15

Aquarium microscope .... 62

Axial images, Oculars for observing 85

Bell-glasses for covering of micro-
scopes 94

BERNHiRD's drawing-table . . 73

Binocular stands 60—65, 109

Blood-counting apparatus . . 81

BOBN-PETEB'S orientation plate . 93

Bottle for immersion oil ... 11

Camera lucida 71

Capillary Rotator 90

Cases for objectives and objective

slides 45

fur the stands 69, 96

Cedar-wood oil as an immersion

fluid 10, 11

Centring appliance 32

Circles, fully divided 79

Collective lens with iris - dia-
phragm 91

Compensating oculars .... 16 — 19

Condenser, achromatic .... 31

„ ordinary 30

„ swing-out .... 30

Cooling trough, ZOTH'S ... 93

Corneal microscope 64, 65

Page

Correction-collar for objectives . 10

Counting-chamber 80

Cover-glasses 94, 95

„ „ for the counting-
chamber .... 80
thickness of . . 8, 42

Cover-glass gauge 79

Cross-line oculars 89

Cross-line micrometer .... 80

Cylinder-diaphragms .... 29, 34

Dark-ground stops etc. ... 29

Defining power of objectives . . 12

Depth, Differentiation of ... 11

Dermatoscope 61, 62

Diffraction apparatus .... 83

Diffraction-plate 83

Drawing apparatus, ABBE'S . ' . 70 — 73

do. for low magnifications . . 67 — 69

Drawing board 74

Drawing prism 68, 71

Drawing tables 73, 74

Draw-tube 42, 43

Drum oculars with micrometer . 76

d<>. with index (Index oculars) 88

Drum fitted with PORRO prisms . 88

Durability of objectives .... 14

EHRLICH'S ocular diaphragms . 80

English Standard Screw ... 12

Engraving name 69

Erecting prism 88

Erecting microscopes

Binocular .
Monocular .

60—65, 109
. 66, 110

Eye-pieces see under Oculars

, Se

I 12

Page

Field, Visible area of object in . 10
Finder appliances on mechanical

stages 36, 38

Finder MALTWOOD'S 93

Fluorite systems 7

Focal depth 11

Focussing the objectives . . . 40 — 42 I

Free working distance ... 8, 16

Gas lamp, incandescent .... 91

Glass cell for the Plankton-searcher 2 1

Glass flask on stand .... 91

Goniometer oculars 78

Haemocytometer 81

Hand-microscope 58

Hand-spectroscope 91

Heating stage 92, 93

HUYGENUN oculars 23, 24

Illuminating apparatus, ABBE'S . 27, 28

do. simplified 33

Illumination by incandescent lamps 25
Illuminating system for small

Stands 33, 34

Image-erecting microscopes,

binocular 60—65, 109

monocular 66—69, 1 10

Immersion fluid 10

Index oculars 88

Iris-cylinder diaphragms . . . 29, 34

Iris-diaphragms 29, 33

do. with ocular 85

Leather travelling cases . . . 56, 69

Magnification

Initial magnification of objectives 14
Ocular magnification .... 17
Tables of magnification

for achromatic objectives with

HUYGENIAN oculars ... 25
for apochromatic objectives

with compensating oculars 19

Page
Tables of magnification

for paired objectives on bin-
ocular stands 26

for the higher powers of
achromatic objectives with

compensating oculars . . 26

MALTWOOD'S Finder 93

Mechanical stage, Large . . . 36, 37

Small ... 38, 39

Metal plate with name engraved 69

Mica films 85

Micro-burner 92

Micrometer oculars 7(J

Micrometer movement . . . 40 — 42

Microscope lamp 91

Microscopes , Complete outfits ,

for bacteriological research . 100, 103
for histological, zoological and

botanical research . . . 100, 104
for mineralogical and cystallo-

graphic research .... 106
for chemical laboratories, apo-
thecaries, breweries, dairies,

paper and celluloid factories 107

for beginners' courses . . . 105, 106

for Customs House .... 108
for opaque objects, metal

specimens etc 108

for travel 56, 103

for Trichinae 58

Micro-spectral objective ... 32

Micro-spectro-photometer . . 88

Micro-spectroscope 87

Microtomes 95

Name, Engraving of, on stand . 69

Numerical aperture 11 — 12

Nose-pieces 43, 44

Objectives

Achromatic 20—23

Apochromatic 12 — 15

Paired for binocular stands . 23

Objective-changers

Oculars :

Analyser

Axial-image

Compensating

Cross-line

Goniometer

HUYGENIAN

Index

Screw-micrometer ....

Spectroscopic

Stereoscopic

with enlarged field of view

for special purposes
Ocular cross-line micrometer .

Ocular micrometer

Orientation plate

Paired Objectives for binocular

Stands

PFEIFFEK'S heating chambers .

„ stage . .

Photo-micrographic stage . .

Plankton-searcher

Polarisers

Polarising apparatus
Preparations, microscopic .
Prism, erecting ........

Prisms, PORRO'S, in drum . . .
Prism Rotator

Resolving power of objectives .
Revolving nose-pieces ....
Rules, measuring

Selenite films

Semi-apochromats

Slides, Object

Page

Page

44, 45 |j Sliding objective-changer . . .

44, 45

Sole-plate and chin-rest . . .

65

84

Spectro-polariser

32

85

Snfifitrosnonfi

91

16 lit Stage, Heating ....

92, 93

89 Ht.fl*rfi m i pr r»m At, Ar

76

78

„ „ cross-line . .

80

23, 24

Stage screw-micrometer . . .

78

88

Stage

36—39

77

Stands:

87

Binocular

60—65

86

Large

46, 47

18, 23

Medium

48—53

86—89

Mineralogical

50, 51

80

Photo-micrographic and pro-

75

jection

46

93

Small

54-59

Stereoscopic camera ....

62, 63

Stops for dark-ground illumination

29

23

92

Tank microscope

62

92

TAst-nlatfi

82

37 Thermo-regulator

92

Thickness, Determination of, by

the micrometer screw . .. .

42

83—85

THOMl's haemoeytometer . . .

81

95

Travelling microscope ....

56

88

Trichinae microscope ....

58

88

Tube-length

8, 9

89, 90

Turn-table

93

12

Vertical illuminator

34, 3r>

43, 44

Vulcanite stage, revolving .

36

79

Warm chambers .

92

Working distance ....

8, 16

7

94 ZoTH's cooling trough ....

93

Printed by Hermann Pohle, Jena.

THIS

«

DATE

AN INITIAL FINE OF 25 CENTS

1 ?NCREASETO SO CENTS ON THE FOURTH
??mi DAY AND ! > ,,.OO ON THE SEVE,

Q H

l

8IQLOGY
LIBRARY

THE UNIVERSITY OF CALIFORNIA LIBRARY