62 Spectra of Metallic Compounds. [January, 



spectroscope made by Desaga, of Heidelberg ; the other a 

 live-prism direct-vision spectroscope made by Hofmann, of 

 Paris. Both were provided with arbitrary photographic 

 scales. The numbers obtained in both cases were reduced 

 to the scale accompanying the coloured drawings of the 

 metallic spectra, by Bunsen and Kirchhoff,* a dash between 

 two numbers indicates a continuity of the spectrum between 

 the points corresponding to them. 



Table of Spectral Lines and Bands. 



Substance. Position of Lines according to Bunsen and Kirchhoff' s Map. 



Cuprous oxide . . .. 37*8 — 44*8 6o*8 — 72-4 78*2 84*1 

 Cupric chloride with V 6o .g_ 72 . 4 



water J ' ^ 



Cupric carbonate . . 39-5 — 43-8—46 — 47*6 60-5—627 67*5 — 74-6 



Cupric acetate . . .. 34-6 43*8 — 46 58 60*5 — 62-7 67-4 68-g — 69-4 70*3 — 72-2 



Cupric sulphate . . 36*6 39-5 — 46 60-5 67-4 69*8 72*2 81-5 84 — 84*5 



Cupric chloride .. 31-8 37*8 40*2 41*4 45 52 6o-8 65-5 68*9 — 73-6 75-9 



— 78*2 81*7 84-1 — 86-4 88-7 — gi 92-2 93-4 94-5 



957 96'9 98 — 102-7 io 5 IQ 8*5 no*8 115-5 H7'8 



121-3 127-1 127-1 129-4 130-6 134-1 136-4 142-2 



i44'5 

 Cupric iodide .. .. 33-6 34-6 36-6 39 41 42-1—43-2 45-5—46 62-7 65 



66-5 68-9—69-9 71-8 73-2 75-1 76 77-5 79 81-3 



82*2 83*2 85-1 — 86-5 89-8—91 94-2 — 95-7 98-5 — 



100 102 — 103-5 104-8 107-3 109-1 — iii-i 114-1 — 



n6*i ng-i — i2o*6 

 Plumbic peroxide . . 55-5 — 58-5 59-5 — 64-2 66-5 — 68*4 6g-g — 71-8 73-6 — 



76 80-3—83-2 

 Plumbic carbonate.. 3g — 43-8 46 — 48-6 53 — 56-5 58-5 — 5g*5 61-5 63-7 66— 



67'g 69-4 — 70*8 72-7 76 79-3 — 82*3 84-1 86-5 

 Plumbic nitrate .. 34*6 37-6 — 40-5 41-1 — 43-8 46 — 48-1 4g-i — 4g-6 54-5 



55'5— 57'58— 59 60-5—64-2 66-5— 67'g 6g-g— 72-2 



74-6 76-5 7g*3— 82-7 88-8— gi-5 

 Plumbic chloride . . 35-6— 40-5 41-6—42-7—43-8 47—48-1 55—57 58-5 



60-5—63-7 66 — 66-5 — 68*4 6g*4 — 71*3 72-2 72-7 



74-1 76-5 77 8i-8 82-2 83-2 84*6 86-5 go*3 g2 



g6-2 101 105-8 108-6 

 Manganous chloride 40*2 — 42*6 47*4— 4g # 8 57— 5g*4 62 — 64-3 — 65-5 — 66*5 



68-g— 74-8 75 -g — 84-1 

 Cadmic nitrate . . 71*3 — 72*2 75-5 — 78 80*3 — 8i-8 88-5 — 8g*8 



In the accompanying map of the spectra of metallic com- 

 pounds the distances on the horizontal divisions of the scale 

 are taken as abscissas, and the relative intensities of the 

 lines and bands as ordinates. It will be seen by comparison 

 of the spectra of the oxygen salts of copper that there is a 

 close similarity between them. Indeed, it is probable that 

 if the drawing had been made directly from the instrument, 

 instead of from notes taken of observations and used in 

 drawing afterwards, the spectra would have been almost 

 identical. The differences would have consisted merely in 

 the breadth and brightness of the lines. But between the 



* Ka=i7*5, Na = 50*4, Li' =31/8, Caa = 42, Ca/3 = 6o-8, Sr£=i05. 



