^:' 



1054 



The Weekly Florists' Review* 



Septbubib is, 1906. 



INFLUENCE OF ACETYLENE. 



(Abstract of a paper by Prof. John Crals, of 

 Cornell Uulreraity, read before the International 

 Acet>lfue AMuvlatlon, July. 19ue.] 



Three types of artificial light have 



been investigated in their relation to 



plant growth since 1861. It was in this 



year that Herv6-mangon, a Frenchman, 



stu«lied the effect of electric light on 



Slant growth. He proved that electric 

 ght could produce chlorophyll and was 

 capable of causing beliotropism. Dr. 

 Seauiotis, of England, carried on a com- 

 prehensive series of experiments in 1879, 

 '80 and '81, during the course of which 

 he demonstrated the injuriuus quality uf 

 the ultra violet rays. Ue conclu«le«l that 

 a 1,400-candle light about ten feet above 

 glass, under which the plants were 

 grown, was about half as efficient as 

 sunlight. 



D^berain continued experiments with 

 arc light in 1889, using a 2,000 naked 

 candle-power. He found the unprotected 

 light injurious, but he also found that 

 the harmful rays could mostly be elimi- 

 nated by using clear glass. His studies 

 did not suggest that there was a promis- 

 ing field for the exploitation of electric 

 light in forcing-house work. 



Studies in electric light, in its relation 

 to plant growth, were instituted at Cor- 

 nell Experiment Station by Bailey in 

 1891 and continued for three or four 

 years. The results of these investiga- 

 tions have been set forth in Bulletins 

 30, 42 and 55. The results were con- 

 flicting; some plants were benefited, 

 while others were injured, without regu- 

 larity or apparent reason. The conclu- 

 sion was reached that electric light pro- 

 motc<l assimilation, hastened growth and 

 maturity; that periods of darkness are 

 not necessary to plant growth; and that 

 it might sometimes be used with profit 

 in certain branches of forcing-house 

 work. 



Electric light as a stimulating agent 

 has not been generally adopted by gar- 

 deners or florists. Its use is exceptional. 

 At the third annual meeting of the So- 

 ciety for Horticultural Science an inter- 

 esting paper was presented by Professor 

 Close, of the Delaware Experimental 

 Station, on the results of his experi- 

 ments with the Cooper-Hewitt mer- 

 cury vapor light, in which be showed the 

 failure of the light to maintain plant 

 growth for any considerable length of 

 time, and also showed the remarkable 

 modification of form which occurred 

 under exclusive illumination of this kind. 



Acetylene Investigations at Cornell. 



The writer has been interested in 

 acetylene as an illuminant since 1896, 

 when he was instrumental in bringing 

 added cheer and comfort to the occu- 

 pants of the rambling Canadian farm 

 homes where his growing days were en- 

 joye<l, by replacing the numerous kero- 

 sene lamps with natty acetylene burners, 

 which have since then continued to act 

 as an important factor in country life. 



Acetylene as an Illuminant. 



The discovery of this gas occurred in 

 1836, but it was not officially christened 

 until 1862. It had no commercial or 

 economic standing until 1892, when a 

 new method of manufacture was dis- 

 covered at the works of Thomas Wilson, 

 Spray, N. C, by Messrs. d'Chalmot and 

 Professor Morehead. The composition 

 of the light rays is the point which 

 directed attention to its possible use 

 as a growth stimulant. Acetylene more 

 nearly approximates sunlight in its 



make-up than apy other artificial illu- 

 minant used, it is composed of the 

 same colors and in very similar degrees 

 of intensity. As for color values.^ of 

 the* »j^etylene rays, let one .. equal * the 

 ji^alue of each color of sunlight, end we 

 have the following comparison by ' Mtln- 

 eterberg: ''^. * * 



Sun. '- .Acetylene. 



Red 1 1.03 



Yellow 1 .1.02 



Green 1 .71 



Blue 1 1.46 



Violet 1 1.07 

 Indlito and orange are not given. 



In electric light studies it has always 

 been found that the chemical ultra vio- 

 let rays were the injurious factors in 

 that illuminant. In the case of the 



Showing Effect of Acetylene. 



(The Tjlly that bad artificial light bloomed three 



we«kB ahead uf the ouh that depended 



on sun alone.) 



acetylene, the ultra violet rays are prac- 

 tically absent, although blue and violet 

 are as strong or stronger than they are 

 found in electric light. 



The Experiments at Cornell. 



The methods of conducting experi- 

 ments with acetylene on plant growth 

 at Cornell University were to add the 

 acetylene illumination to the dayligiic 

 illumination by turning on the former 

 after twilight fell. We endeavored to 

 make comparisons on the influence of 

 this light under different conditions, so 

 that a warm, a medium and a cool house 

 were used. 



Temperature of warm house 60 to 65 

 degrees at night; soil area, 235 square 

 feet; 410 candle-power; five feet from 

 ground. 



Temperature of cool house, 45 to 50 

 degrees at night; soil area, 129 square 

 feet; 350 candle-power; three feet from 

 ground. 



Temperature of medium house, 60 to 

 55 degrees at night; 100 square feet; 

 270 candle-power; two feet from bench. 



I hftv^ pleasure in acknowledging val- 

 uable aissistanee from the following 

 flrms, who furnished acetylene genera- 

 tors: Badiant Acetylene Generator Co., 

 Canandaigua, N. Y.; Monarch Acetylene 

 Co., Buffalo, N. Y.; Davis Acetylene 

 Generator Co., Elkhart, Ind.; Sunlight 

 Gaa Machine Co., New York City. 



From the following bouses, who fur- 

 nished burners and other fixtures: W. 

 M. Crane Co., New York City; Drake 

 Acetylene Burners & Supply Co., Cleve- 

 land, O.; State Line Co. and American 

 Lava Co., Chattanooga, Tenn.; J. B. 

 Carroll, Chicago, 111. Finally the ex- 

 periments were made possible by the 

 generous aid of the Union Carbide Co., 

 which supplied practically all the carbide 

 used, about two and one-half tons. 



I should make it clear at the outset 

 that while the main features of the ex- 

 periments were planned and directed by 

 the writer, the execution of the details, 

 the making of the daily records and 

 the comjiilation of these records were 

 carried out by M. J. lorns, who under- 

 took the task as a major problem for a 

 Ph. D. degree in the department of hor- 

 ticulture. The investigation covered two 

 university years. 



Scope: The lights in two houses were 

 run nearly 5,000 hours, during which 

 time something over two and one-half 

 tons of carbide were used. In making 

 the investigation 150 plant forms, em- 

 bracing twenty-five families, fifty genera 

 and sixty-five species were employed. 



General results; Influence on top 

 growth for culinary use; most of the 

 salad plants were studied. Lettuce, pars- 

 ley and spinach were considerably hast- 

 ened. The seeding period was also ac- 

 celerated. The plants under acetylene 

 were crisper and apparently more succu- 

 lent than those grown under sun alone. 



Plants Grown for Foliage. 



Coleus: The vigor of the plant was 

 increased, but no other marke<l change, 

 either as to color or consistency of 

 foliage, was noted. 



Asparagus Sprengeri and plumosus: 

 Yerj little, if any, difference was ob- 

 served between the plants in sun and 

 those in acetylene. Such difference as 

 was noted was in favor of the acetylene 

 plants. 



Begonias, Bex and tuberous: With 

 both types the vegetative growth was 

 considerably stronger under acetylene 

 than under sun alone, but in most cases 

 the flowering period was materially de- 

 layed. This might be an advantage in 

 the case of the Bex type, but would be 

 a disadvantage in case of the tuberous 

 varieties grown primarily for flowers. 



Cobsea scandens: This produced fif- 

 teen to twenty per cent more vine under 

 acetylene than under sun alone. No other 

 modification was observed. 



Ferns: These did not show any 

 marked difference, except in the matter 

 of color, which was lighter in the plants 

 under acetylene than those under sun. 



In these crops and in some of those 

 following, electric light was contrasted 

 with acetylene: 



Root Crops. 



Leeks: Here again very little diffe- 

 rence was noted between plants grown 

 under acetylene and plants grown under 

 electric light. Both series were a little 

 ahead of those under sun only. 



Onions: Very slight differences. Elec- 



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