Ci^e ^ojittlar ^citnce ^tto0 



AND 



BOSTON JOURNAL OF CHEMISTRY. 



Volume •XXIII. 



BOSTON, JULY, 1889. 



Number 7. 



CONTENTS. 



Familiar Science.^ — The Eiflfel Tower 



A Miniature Altar 



Barometers 



Evolution 



Interesting Scientific Exliibits 

 Why Sixty Seconds Make a Minute 

 Cave-Dwellers in Mexico .... 

 Scientific Brevities 



A 



97 

 97 

 97 

 98 



99 

 100 

 100 

 100 



lOI 

 lOI 



102 

 102 



Practical Chemistry and the Arts 



Cliinese Derrick 



On Allotropic Forms of Silver 



Practiail Recipes 



Laboratory Notes 



Home, Farm, and Garden. — Vegetables and 



Fruits 



Silica in Plants 



A Botanical Puzzle 



Care of the Hair 



Culinary Recipes 



Gleanings 



Editorial. — Fourth of July ...... 



A Hibernating Fish 



The Paris Exhibition 



Meteorology for May, 18S9, with Review of 



the Spring 



Astronomical Phenomena for July, 1889 . . 

 Literary Notes 



Medicine and Pharmacy. — Hints About 



Health 



Rabies, or Hydrophobia 



Monthly Summary of Medical Progress . . 



The American Posture 



How to Treat Burns 



Credulity and "Christian Science" .... 



Licorice Root 



Humors 



Publishers' Column 112 



103 

 103 

 ■03 

 104 

 104 

 104 



105 

 106 

 107 



107 

 108 

 108 



109 

 109 

 no 

 III 

 112 

 112 

 112 

 112 



Eanjlliar Science. 



THE EIFFEL TOWER. 



Ev'EK since the unfortunate collapse of the 

 Tower of Babel enterprise, it has been a 

 favorite pursuit with mankind to vie with 

 each other in erecting structures of great 

 height. For a long time, the great pyramid 

 of Egypt was the highest artificial .structure 

 in existence, but its height of 477 feet is 

 now exceeded by the Cathedral of Cologne 

 ('517 feet) and the Washington Monument 

 (553 feet.) 



The Eiffel Tower, however, leaves all other 

 monuments far below it, and will probably 

 never be overshadowed. It was the brilliant 

 conception of a French engineer, and has not 

 only proved a great success from an engineer- 

 ing point of view, but has a degree of sym- 

 metry and artistic beauty rather surprising in 

 a tower erected for no other purpose than to 

 reach a certain height above the ground. 



The Eift'el Tower is 300 metres (984 feet) 

 high, and is built throughout of iron beams 

 and girders. Access is obtained to the differ- 

 ent galleries by several systems of elevators, 

 including the well-known "Otis" elevators of 



American manufacture. It will undoubtedly 

 be one of the principal attractions of the Paris 

 Exposition the present summer, and ma}' 

 afterwards be of some practical use as a me- 

 teorological observatory, and for various sci- 

 entific investigations. 



The accompanying illustration gives a gen- 

 eral view of the construction of the tower, 

 and its comparative height with other cele- 

 brated architectural monuments. No. i is 

 the Vendome Column at Paris, 147 feet ; 2, 



the towers of Notre Dame, 215 feet; 3, the 

 Column of July, 153 feet; 4, Saint Peter's 

 Cathedral at Rome, 431 feet; 5, the Wash- 

 ington Monument, 552 feet ; 6, the Great 

 Pyramid, 477 feet ; 7, Rouen Cathedral, 490 

 feet ; 8, Strasbourg Cathedral, 465 feet. It 

 will thus be seen that the Eiffel Tower is not 

 only almost twice as high as any other build- 

 ing, but exceeds any natural elevation within 

 a circle of many miles around Paris. 



A MINIATURE ALTAR. 



The nine pieces of paper represented in 

 the accompanying illustration (Fig. i) form a 

 very good representation of a cross placed 

 upon an altar, and flanked by two lighted 

 candles. The curious part of it, however, 

 is that all these pieces can be cut out of one 

 piece of paper by a single stroke of the 



scissors. This remarkable residt is obtained 

 by folding the paper, before cutting, as shown 

 in Fig. 2. 



Fig. I. 



Take an oblong piece of soft paper, like 

 No. I, and fold it lengthwi.sc, with the fold to 

 the left (No. 2.) Then turn down the top 

 part horizontally (No. 3), and again turn 

 down the upper right-hand corner, as shown 

 in No. 4. Fold the whole piece of paper 

 vertically once more, with the fold to the 

 right, and No. 5 will be obtained, which a 

 single stroke of the scissors, lengthwise in the 

 direction of the dotted line, will separate into 



Fig. 2. 



the cross and other pieces figured above. 

 This is quite an old trick, but a very inge- 

 nious and entertaining one. 



BAROMETERS. 



If we plunge our hand deeply into water, 

 we feel a pressure upon it, due to the weight 

 of the water above it, and every boy who 

 goes in swimming knows how painful this 

 pressure may become upon the drum of the 

 ear when diving into deep water. So in 

 the ocean o£ air which surrounds the earth, 

 and at the bottom of which we live ; its pres- 

 sure is continually exerted upon our bodies 



