OL. 21 



10. 24 



A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE 



' ' To the solid ground 



nind which builds j\>r aye." — WORDSWORTH 



Of Nature trusts th 



MACMILLAN & CO., Publishers, 



Bond St., NEW YOEK. 



THURSDAY, APRIL 15, 1! 



Price 15 Cents 

 Annual Subscription $6 



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to 



8 



S3 



.8 



3 



so 



Our Priced and Illustrated Catalogue will be published in four parts, any or all of which will be mailed on application. 



irt 1st— Mathematical Instruments, ido pages ; contains list and prices of Drawing Implements, Drawing Materials, 

 Pocket Compasses, Surveying Compasses, Engineers' Transits and Levels. Surveying Chains, Tape Meas- 

 ures. Pocket Rules, and Books relating to Drawing, Engineering, and Mechanics. 



rt 2d— Optical Instruments, 144 pages ; contains list and prices of Spectacles, Eye-glasses, Lenses, Spyglasses, 

 Telescopes, Opera and Field Glasses, Graphoscopes, Stereoscopes, Came'ra-Obscuras, Camera-Lucidas, 

 Microscopes, Microscopic Preparations, and Books on Optics and Microscopy. 



rt 3d— Magic Lanterns and Slides, 112 pages; contains list and prices of Magic Lanterns for Toys, for Public and 

 Private Exhibitions, Sciopticons, Stereopticons, Scientific Lanterns, and accessory apparatus to be used 

 with them ; Magic Lantern Slides, both colored and uncolored. 



rt 4th— Physical Instruments, 188 pages ; contains list and prices of Instruments to illustrate Lectures in every 

 department of Physics and Chemical Science, Air Pumps, Electric Machines, Galvanic Batteries, Barome- 

 ters, Thermometers, Rain Gauges, Globes, Spectroscopes, Auzoux's Anatomical Models, and Books relat- 

 ing to Scientific Subjects. 



JAMES W. QUEEN & CO., 



Mathematical. Optical, and Philosophical Instrument Makers, 

 024 Chestnut Street, Philadelphia. 



