Use 



FLO Rl GENE 



(A registered Name 

 suggested by 

 FLOOR HYCIENE) 



ODOURLESS or powerful GERMICIDAL Floor luid. 



On all Laboratory, School, Library, Museum, Studio, Office, andothei Floors— eithei Wood, Linoleum, 

 Stone, Concrete, or Polished, etc.— for the anhydrous "WEIGHTING" and LAYING of 



DUST 



(As recommended in tin- Education Dept. IMue Boole.) 



' ' Florigcne " need only be applied three times a year, as e:u li application l.i^ts for two t" six 



months, according to wear. The ordinary daily sweeping .done required to clean the floors no 



scrubbing {unless preferred), or sprinkling of any kind — therefore no injurious moisture. Apparatus, 



Hooks, Furniture, etc., seldom require Dusting or Cleaning. 



Send for Particulars. Bacteriological and other Reports, and Testimonials to — 



The "DUS T-ALLAYER" Co., 165, Queen Victoria Street, Lond on, E.C 



*^^ | Contractors to Admiralty, War oilier, H.M. Office of Works, etc. 



J. SWIFT A SON 



MANUFACTURING OPTICIANS TO H.M. GOVERNMENT. 

 SEVEN GOLD MEDALS awarded for OPTICAL EXCELLENCE. 



NEW RESEARCH 

 MICROSCOPE, 



With 



7/ convph i' mechanical 

 movements. 





Price fitted with Triple Dustproof 

 Nosepiece, Abbe Condenser with Iris 

 Diaphragm, Two Oculars, jj in., \ in., 

 and T '., in. Oil Immersion objectives, 

 in Cabinet . . . . £21 O O 



N.B. 



IMPROVED l« 

 UNIVERSITY MICROSCOPE 



Price fitted with 1 in. and \ in. 



or ,'. in. objectives, one Ocular and 

 Iris Diaphragm, inCabinet, £9 10 O 



Binocular arrangement, extra, £2 12s, 

 Patent Mechanical Stage, £2 10s. 



An Ideal Instrument for Professional 

 or Amateur, 



The ,'■-/«. Objectives supplied with these Microscopes will work through the thicker of 

 the two cover glasses supplied with the Thoma-Zeiss Hemacytometer. 



UNIVERSITY OPTICAL WORKS, 

 81, Tottenham Court Road, LONDON. 



THE HEREDITY OF ACQUIRED 

 CHARACTERS IN PLANTS. 



An Aspect of the true Darwinism based on Personal Observations 



and Experiments. 



By the Rev. Prof. GEORGE HENSLOW. 



With Illustrations. Demy 8vo. 6s. net. 

 JOHN MURRAY, ALBEMARLE STREET, W. 



( xi ) 



