US3204964A - Method of demonstrating stroboscopic effect - Google Patents

Method of demonstrating stroboscopic effect Download PDF

Info

Publication number
US3204964A
US3204964A US375119A US37511964A US3204964A US 3204964 A US3204964 A US 3204964A US 375119 A US375119 A US 375119A US 37511964 A US37511964 A US 37511964A US 3204964 A US3204964 A US 3204964A
Authority
US
United States
Prior art keywords
toy
balloon
disks
speed
demonstrating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US375119A
Inventor
John J Geary
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US375119A priority Critical patent/US3204964A/en
Application granted granted Critical
Publication of US3204964A publication Critical patent/US3204964A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09BEDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
    • G09B23/00Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes
    • G09B23/06Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics
    • G09B23/22Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics for optics
    • AHUMAN NECESSITIES
    • A63SPORTS; GAMES; AMUSEMENTS
    • A63JDEVICES FOR THEATRES, CIRCUSES, OR THE LIKE; CONJURING APPLIANCES OR THE LIKE
    • A63J15/00Peep-shows, e.g. raree-shows; Kaleidoscopic or other opalescence exhibitions
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00Stock material or miscellaneous articles
    • Y10S428/913Material designed to be responsive to temperature, light, moisture

Definitions

  • One or the principal objects of the invention is to provide an amusing and interesting toy which appeals to all age levels, being not only highly entertaining to operate and to watch, but also serving to demonstrate a number of physical laws and principles.
  • Another object is to provide such a toy which can be used indoors or outdoors and which is safe.
  • Another object is to provide such a toy which teaches muscular coordination and provides manual exercise.
  • a specific object of the invention is to provide such a toy which simulates orbiting or the earth by a space vehicle, particularly by a pair of space vehicles, the operation of the toy illustrating how the space vehicles join each other to orbit as a single unit.
  • Another object of the present invention is to illustrate either the particular land and water areas over which an astronaut orbits when orbiting in a particular path, or the constellations under which a space vehicle travels when orbiting in a particular path.
  • Another object of the invention is to provide such a toy which can be used as a stroboscope, that is, as an instrument for viewing moving objects so that they appear to be stationary or to advance or retreat slower than their actual speed.
  • Another object is to provide such a toy which is eX- tremely low in cost.
  • Another object is to provide such a visible toy which can be put into serviceable condition and operated by very young children having little manual dexterity.
  • Another specific object of the invention is to provide means whereby a particular orbit can be observed, achieved or maintained.
  • FIG. 1 is a side elevational view of a visual toy embodying the present invention.
  • FIG. 2 is a fragmentary enlarged sectional view taken on line 22, FIG. 1.
  • FIG. 3 is a top plan view of a modified form of the invention.
  • the numeral 5 represents a transparent rubber balloon inflated with a gas, such as air, it being an important feature of the invention that the wall of the inflated balloon be transparent so that the operation of the part or parts contained in the balloon can be visually observed.
  • the balloon 5 is provided with the conventional outwardly projecting neck 6 through which the balloon is inflated and any form of stopper 7 can be employed for closing this neck after the balloon has been inflated and to maintain it in an inflated condition.
  • the balloon 5 is in the form of a terrestrial globe, having imprinted thereon the continents 8 of the world in such manner as not to destroy the transparency of the Wall of the balloon and the ability to observe visually the action of the circular members contained within the balloon.
  • diametral circular lines 9, 10 and 11 can be imprinted on the balloon in planes to serve as targets in the manner hereinafter described. These circular lines can be of different colors, say, red, yellow and white.
  • These circular members are in the form of disks each having a plastic body 13; While these disks can be of any suitable form they are shown as flat disks with center holes 14 and rims 15. They can,- however, be made of any fanciful form such as being made in simulation of present concepts of space stations including an outer annular rirn, spokes and an inner annular hub ring. Itis also an important feature of the invention that the disks 12 are specially manufactured of a fluorescent material which is capable of being activated by exposure to a fluorescent light or to daylight. This material can be of different colors for different disks.
  • the disks 12 are preferably substantially larger than the passage through the filling neck 6 and this neck is distended in order to insert the disks into the rubber toy balloon 5, there preferably being two such disks. contained within the balloon.
  • a visual toy so constructed has a number of highly entertaining and interesting uses, particularly as related to space vehicles orbiting the earth.
  • the wall of the inflated rubber toy balloon 5 is transparent, the contained disks 12 are clearly visible therein.
  • these disks are put into circular. orbitwith their rims 15 rolling around the inner surface of the toy inflated balloon 5 in circular paths indicated by the dotted lines 18 and 19.
  • These paths can be difierent, as illustrated, but not only do the paths tend to merge into each other but the disks may be manuevered to join each other and travel around side by side in the manner of a pair of astronauts joining each other in orbiting around the earth. This joinder is accomplished by exerting a slight manual pressure against the bottom of the balloon to render the balloon slightly non-spherical which condition causes the vehicles to catch up with each other.
  • the inflated toy balloon being in the form of a terrestrial globe or the continents 8 imprinted thereon in such manner as not to interfere with viewing the contained disks 12, the land masses and oceans over which an astronaut travels is clearly illustrated and it is possible to gyrate the inflated balloon in such manner as to simulate the path of a particular space vehicle.
  • the colored diametral lines 9, 10 and 11 can be used as targets, that is, the balloon can be gyrated in such manner as to cause the disks 12 to travel along a particular one of these diametral lines, or to shift from one line to another.
  • the presence of the fluorescent material is not merely to render the orbiting of the disks 12 visible at night, although it will be appreciated that such use provides a highly interesting spectacle.
  • Another highly important result flowing from the glow illumination provided by the fluorescent material 16 is using the visual toy as a stroboscope, that is, as an instrument for viewing the orbiting luminescent disks 12 so that they appear to be stationary or so that they appear to either advance or back up very slowly.
  • This stroboscope eflect can be achieved by operating the toy in the manner above described in the presence of an intermittent source of light, such as a television set or a fluorescent light fixture.
  • the toy can also be used as a stroboscope under a fluorescent light operating at a frequency of, say, 60 cycles per second.
  • a fluorescent light bulb produces an intermittent source of light at that frequency and when the toy is gyrated so as to cause the disks 12 to orbit at that frequency they will appear to be stationary.
  • FIG. 3 The form of the invention illustrated in FIG. 3 is identical with the form of the invention shown in FIGS. 1 and 2 except that instead of the transparent inflated rubber toy balloon 5a being in the form of a terrestrial globe, it is in the form of a celestial map globe, the stars So of the northern hemisphere being illustrated in the top plan view, FIG. 3.
  • the same fluorescent disks 12 are employed in the same manner and hence the same reference numerals have been applied to these disks and their path around the interior of the inflated toy balloon is indicated by the dot-dash line 18a. It will be seen that with the modification illustrated in FIG. 3, instead of demonstrating the land and Water areas over which a vehicle passes in orbiting the earth, the constellation of the northern and southern hemispheres under which it passes are demonstrated.
  • the mapped land masses 8, or the mapped stars So constitute visible indicia whereby a particular orbit can be observed, selected or maintained and is achieved, broadly, by the provision of visible indicia extending over a substantial part of the area of the balloon and serving as a reference for the orbital path of the disks 12.
  • the method of demonstrating stroboscopic effect with a toy having a transparent body of globular form containing a circular luminescent member visible from the exterior thereof which comprises gyrating said body in light of pulsating intensity to set said circular member into motion to follow an orbital path around the inner surface of said body, such gyration being at such speed as to cause said member to appear to stand still at an orbital speed synchronized with the pulsations of said light, to slowly advance with increased orbital speed, and to slowly back up with descreased orbital speed.
  • the source of intermittent light is a television receiver wherein the intermittent light comprises the number of frames per second scanned by the cathode beam of the receiver.
  • the source of intermittent light is a fluorescent light tube operating to produce such intermittent light at the frequency of the alternating current energizing the tube.

Description

Sept. 7, 1965 J. J. GEARY METHOD OF DEMONSTRATING STROBOSCOPIC EFFECT Filed June 15. 1964 Ill llllllll llllllllllllL.
INVENTOR.
United States Patent Office 3,204,964 Patented Sept. 7, 1965 1 ,20 ,9 METHOD OF DEMONSTRATING STROBOSCOPIC v EFFECT John J. Gea'i'y, 71 Dexter Terrace, Tonawanda, NY. Filed June 15, 1964, Ser. No. 375,119 3 Claims. (Cl. 273-109) This invention relates to method of demonstrating strcbo'scopic efiect with a visual toy which is not only highly entertaining but also demonstrates a number of additional physical laws, particularly those related to manned or unmanned orbiting vehicles of the earth.
One or the principal objects of the invention is to provide an amusing and interesting toy which appeals to all age levels, being not only highly entertaining to operate and to watch, but also serving to demonstrate a number of physical laws and principles.
Another object is to provide such a toy which can be used indoors or outdoors and which is safe.
Another object is to provide such a toy which teaches muscular coordination and provides manual exercise. A specific object of the invention is to provide such a toy which simulates orbiting or the earth by a space vehicle, particularly by a pair of space vehicles, the operation of the toy illustrating how the space vehicles join each other to orbit as a single unit.
Another object of the present invention is to illustrate either the particular land and water areas over which an astronaut orbits when orbiting in a particular path, or the constellations under which a space vehicle travels when orbiting in a particular path.
Another object of the invention is to provide such a toy which can be used as a stroboscope, that is, as an instrument for viewing moving objects so that they appear to be stationary or to advance or retreat slower than their actual speed.
Another object is to provide such a toy which is eX- tremely low in cost.
Another object is to provide such a visible toy which can be put into serviceable condition and operated by very young children having little manual dexterity.
Another specific object of the invention is to provide means whereby a particular orbit can be observed, achieved or maintained.
Other objects and advantages of the invention will be apparent from the following description and drawings in which:
FIG. 1 is a side elevational view of a visual toy embodying the present invention.
FIG. 2 is a fragmentary enlarged sectional view taken on line 22, FIG. 1.
FIG. 3 is a top plan view of a modified form of the invention.
In the form of the invention shown in FIGS. 1 and 2, the numeral 5 represents a transparent rubber balloon inflated with a gas, such as air, it being an important feature of the invention that the wall of the inflated balloon be transparent so that the operation of the part or parts contained in the balloon can be visually observed. The balloon 5 is provided with the conventional outwardly projecting neck 6 through which the balloon is inflated and any form of stopper 7 can be employed for closing this neck after the balloon has been inflated and to maintain it in an inflated condition. In the form of the invention shown in FIGS. 1 and 3, the balloon 5 is in the form of a terrestrial globe, having imprinted thereon the continents 8 of the world in such manner as not to destroy the transparency of the Wall of the balloon and the ability to observe visually the action of the circular members contained within the balloon.
Additionally, diametral circular lines 9, 10 and 11 can be imprinted on the balloon in planes to serve as targets in the manner hereinafter described. These circular lines can be of different colors, say, red, yellow and white.
These circular members, indicated generally at 12, are in the form of disks each having a plastic body 13; While these disks can be of any suitable form they are shown as flat disks with center holes 14 and rims 15. They can,- however, be made of any fanciful form such as being made in simulation of present concepts of space stations including an outer annular rirn, spokes and an inner annular hub ring. Itis also an important feature of the invention that the disks 12 are specially manufactured of a fluorescent material which is capable of being activated by exposure to a fluorescent light or to daylight. This material can be of different colors for different disks. The disks 12 are preferably substantially larger than the passage through the filling neck 6 and this neck is distended in order to insert the disks into the rubber toy balloon 5, there preferably being two such disks. contained within the balloon.
A visual toy so constructed has a number of highly entertaining and interesting uses, particularly as related to space vehicles orbiting the earth.
Thus, since the wall of the inflated rubber toy balloon 5 is transparent, the contained disks 12 are clearly visible therein. By manually gyrating the balloon, these disks are put into circular. orbitwith their rims 15 rolling around the inner surface of the toy inflated balloon 5 in circular paths indicated by the dotted lines 18 and 19. These paths can be difierent, as illustrated, but not only do the paths tend to merge into each other but the disks may be manuevered to join each other and travel around side by side in the manner of a pair of astronauts joining each other in orbiting around the earth. This joinder is accomplished by exerting a slight manual pressure against the bottom of the balloon to render the balloon slightly non-spherical which condition causes the vehicles to catch up with each other.
Due to the inflated toy balloon being in the form of a terrestrial globe or the continents 8 imprinted thereon in such manner as not to interfere with viewing the contained disks 12, the land masses and oceans over which an astronaut travels is clearly illustrated and it is possible to gyrate the inflated balloon in such manner as to simulate the path of a particular space vehicle.
As a test of skill, the colored diametral lines 9, 10 and 11 can be used as targets, that is, the balloon can be gyrated in such manner as to cause the disks 12 to travel along a particular one of these diametral lines, or to shift from one line to another.
The presence of the fluorescent material is not merely to render the orbiting of the disks 12 visible at night, although it will be appreciated that such use provides a highly interesting spectacle. Another highly important result flowing from the glow illumination provided by the fluorescent material 16 is using the visual toy as a stroboscope, that is, as an instrument for viewing the orbiting luminescent disks 12 so that they appear to be stationary or so that they appear to either advance or back up very slowly. This stroboscope eflect can be achieved by operating the toy in the manner above described in the presence of an intermittent source of light, such as a television set or a fluorescent light fixture. When the toy is brought into action in the front of a television set where scanning takes place at the rate of 30 frames per second, when the balloon 5 is gyrated at such a speed as to cause the disks 12 to orbit at a speed of 30 frames per second, they will appear .to be stationary. As their speed of orbiting is increased slightly or dies down, they will appear to advance or back up at a correspondingly slow speed as compared with their actual speed of gyration.
The toy can also be used as a stroboscope under a fluorescent light operating at a frequency of, say, 60 cycles per second. A fluorescent light bulb produces an intermittent source of light at that frequency and when the toy is gyrated so as to cause the disks 12 to orbit at that frequency they will appear to be stationary.
The form of the invention illustrated in FIG. 3 is identical with the form of the invention shown in FIGS. 1 and 2 except that instead of the transparent inflated rubber toy balloon 5a being in the form of a terrestrial globe, it is in the form of a celestial map globe, the stars So of the northern hemisphere being illustrated in the top plan view, FIG. 3. The same fluorescent disks 12 are employed in the same manner and hence the same reference numerals have been applied to these disks and their path around the interior of the inflated toy balloon is indicated by the dot-dash line 18a. It will be seen that with the modification illustrated in FIG. 3, instead of demonstrating the land and Water areas over which a vehicle passes in orbiting the earth, the constellation of the northern and southern hemispheres under which it passes are demonstrated.
It will be seen that either the visible lines 9, 10, 11,
the mapped land masses 8, or the mapped stars So constitute visible indicia whereby a particular orbit can be observed, selected or maintained and is achieved, broadly, by the provision of visible indicia extending over a substantial part of the area of the balloon and serving as a reference for the orbital path of the disks 12.
From the foregoing it will be seen that the present invention has the unique advantages and accomplishes the various objects previously set forth.
I claim:
1. The method of demonstrating stroboscopic effect with a toy having a transparent body of globular form containing a circular luminescent member visible from the exterior thereof, which comprises gyrating said body in light of pulsating intensity to set said circular member into motion to follow an orbital path around the inner surface of said body, such gyration being at such speed as to cause said member to appear to stand still at an orbital speed synchronized with the pulsations of said light, to slowly advance with increased orbital speed, and to slowly back up with descreased orbital speed.
2. The method set forth in claim 1 wherein the source of intermittent light is a television receiver wherein the intermittent light comprises the number of frames per second scanned by the cathode beam of the receiver.
3. The method set forth in claim 1 wherein the source of intermittent light is a fluorescent light tube operating to produce such intermittent light at the frequency of the alternating current energizing the tube.
References Cited by the Examiner UNITED STATES PATENTS 1,206,867 12/16 Lewis 4689 2,201,486 5/40 Gold 4688 X 2,418,651 4/47 MauSshardt 88l4 2,644,890 7/53 Hollihan 273109 X 2,927,383 3/60 Longino 4688 X RICHARD C. PINKHAM, Primary Examiner.

Claims (1)

1. THE METHOD OF DEMONSTRATING STROBOSCOPIC EFFECT WITH A TOY HAVING A TRANSPORT BODY OF GLOBULAR FORM CONTAINING A CIRCULAR LUMINESCENT MEMBER VISIBLE FROM THE EXTERIOR THEREOF, WHICH COMPRISES GYRATING SAID BODY IN LIGHT OF PULSATING INTENSITY TO SET SAID CIRCULAR MEMBER INTO MOTION TO FOLLOW AN ORBITAL PATH AROUND IN THE INNER SURFACE OF SAID BODY, SUCH GYRATION BEING AT SUCH SPEED AS TO CAUSE SAID MEMBER TO APPEAR TO STAND STILL AT AN ORBITAL SPEED SYNCHRONIZED WITH THE PULSATIONS OF SAID LIGHT, TO SLOWLY ADVANCE WITH INCREASED ORBITAL SPEED, AND TO SLOWLY BACK UP WITH DESCREASED ORBITAL SPEED.
US375119A 1964-06-15 1964-06-15 Method of demonstrating stroboscopic effect Expired - Lifetime US3204964A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US375119A US3204964A (en) 1964-06-15 1964-06-15 Method of demonstrating stroboscopic effect

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US375119A US3204964A (en) 1964-06-15 1964-06-15 Method of demonstrating stroboscopic effect

Publications (1)

Publication Number Publication Date
US3204964A true US3204964A (en) 1965-09-07

Family

ID=23479578

Family Applications (1)

Application Number Title Priority Date Filing Date
US375119A Expired - Lifetime US3204964A (en) 1964-06-15 1964-06-15 Method of demonstrating stroboscopic effect

Country Status (1)

Country Link
US (1) US3204964A (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3317209A (en) * 1964-12-22 1967-05-02 John W Dixon Educational device
US3423872A (en) * 1963-11-15 1969-01-28 Ashford B Dodson Transparent sphere with rotating balls therein
US3465470A (en) * 1964-10-12 1969-09-09 Frank G Jordan Game devices
US3623728A (en) * 1969-03-14 1971-11-30 A Eddy Goldfarb Inflatable pillow with game board
US3666269A (en) * 1970-06-05 1972-05-30 David W Gilchrist Spherical game
US3683526A (en) * 1970-06-08 1972-08-15 Tibor Horvath Optical display device
US3738658A (en) * 1971-09-17 1973-06-12 R Smith Disk rotating game
US3806123A (en) * 1972-09-27 1974-04-23 J Fennell Body mounted amusement device
US4595369A (en) * 1985-03-08 1986-06-17 Downs Arthur R Educational and amusement device
FR2650687A1 (en) * 1989-08-03 1991-02-08 Madi Ahmed Demonstration, manipulation and educative device for studies in optics of colours and of stroboscopy
US5862619A (en) * 1996-11-26 1999-01-26 Stancil; Jeffrey T. Animated water fowl decoy
USD977044S1 (en) * 2020-05-11 2023-01-31 Gary Kemp Inflatable zeotrope ball

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1206867A (en) * 1916-03-28 1916-12-05 Jewel Lewis Educational toy.
US2201486A (en) * 1938-09-15 1940-05-21 Gold Samuel Toy
US2418651A (en) * 1944-08-28 1947-04-08 Milton R Mausshardt Optical device for indicating correct operating speed of phonograph turntables
US2644890A (en) * 1949-04-07 1953-07-07 Hollihan Mathilda Ramona Amusement device
US2927383A (en) * 1958-06-03 1960-03-08 Hugh A Longino Balloon world satellite

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1206867A (en) * 1916-03-28 1916-12-05 Jewel Lewis Educational toy.
US2201486A (en) * 1938-09-15 1940-05-21 Gold Samuel Toy
US2418651A (en) * 1944-08-28 1947-04-08 Milton R Mausshardt Optical device for indicating correct operating speed of phonograph turntables
US2644890A (en) * 1949-04-07 1953-07-07 Hollihan Mathilda Ramona Amusement device
US2927383A (en) * 1958-06-03 1960-03-08 Hugh A Longino Balloon world satellite

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3423872A (en) * 1963-11-15 1969-01-28 Ashford B Dodson Transparent sphere with rotating balls therein
US3465470A (en) * 1964-10-12 1969-09-09 Frank G Jordan Game devices
US3317209A (en) * 1964-12-22 1967-05-02 John W Dixon Educational device
US3623728A (en) * 1969-03-14 1971-11-30 A Eddy Goldfarb Inflatable pillow with game board
US3666269A (en) * 1970-06-05 1972-05-30 David W Gilchrist Spherical game
US3683526A (en) * 1970-06-08 1972-08-15 Tibor Horvath Optical display device
US3738658A (en) * 1971-09-17 1973-06-12 R Smith Disk rotating game
US3806123A (en) * 1972-09-27 1974-04-23 J Fennell Body mounted amusement device
US4595369A (en) * 1985-03-08 1986-06-17 Downs Arthur R Educational and amusement device
FR2650687A1 (en) * 1989-08-03 1991-02-08 Madi Ahmed Demonstration, manipulation and educative device for studies in optics of colours and of stroboscopy
US5862619A (en) * 1996-11-26 1999-01-26 Stancil; Jeffrey T. Animated water fowl decoy
USD977044S1 (en) * 2020-05-11 2023-01-31 Gary Kemp Inflatable zeotrope ball

Similar Documents

Publication Publication Date Title
US3204964A (en) Method of demonstrating stroboscopic effect
Collin The theory of celestial influence
Plait Bad astronomy: misconceptions and misuses revealed, from astrology to the moon landing" hoax"
US3423872A (en) Transparent sphere with rotating balls therein
US3528659A (en) Aerial projectile toy
US3520073A (en) Multifunction astronomical display planetarium
US3055124A (en) Terrestrial globe, and method of manufacturing the same
US3707786A (en) Method and means of presenting a planetarium display
Dick Celestial scenery: or, The wonders of the planetary system displayed
Adams Lectures on natural and experimental philosophy
US2791853A (en) Animated display
Mitchel Popular Astronomy: A Concise Elementary Treatise on the Sun, Planets, Satellites and Comets
Hockey How We See the Sky: A Naked-Eye Tour of Day and Night
US2492691A (en) Illuminated world globe
Davidson Sky phenomena: A guide to naked-eye observation of the stars
CN209765899U (en) Children cognitive dynamic planet simulation display stand
US1384801A (en) Educational apparatus
CN2212231Y (en) Solar system celestial body movement globe
US3718992A (en) Self-contained planetarium
JPH10211363A (en) Ferris wheel
Verriest Life, eye disease and work of Joseph Plateau
Mitchel The Planetary and Stellar Worlds: An Exposition of the Discoveries and Theories of Modern Astronomy
Mitchel The Orbs of Heaven..
Zhang An Adventure: Weightlessness Phenomena and Life on Space Station
Mattison A High-school Astronomy: In which the Descriptive, Physical, and Practical are Combined, with Special Reference to the Wants of Academies and Seminaries of Learning