THE THRESHOLD OF SCIENCE: 



A VARIETY OF 



Simple anfc amusing Experiments 



ILLUSTRATING 



SOME OF THE CHIEF PHYSICAL AND CHEMICAL 



PROPERTIES OF SURROUNDING OBJECTS, 

 AND THE EFFECTS UPON THEM OF LIGHT AND HE A T. 



BY 



C. R. ALDER WRIGHT, 



\\ 



D.SC. (LOND.), B.SC. (VICT.), F.R.S., 



LECTURER ON CHEMISTRY AND PHYSICS IN ST MARY'S HOSPITAL MEDICAL SCHOOL, LONDON. 



Witl) fCwmerottS Illustrations. 



CHARLES GRIFFIN AND COMPANY, 

 EXETER STREET, STRAND. 



1891. 



