Variations in Technique
A number of variations in procedure that do not decrease the sensitivity of the method can be adopted.
- Ant concentration of sap that the paper can absorb can ve used. The stronger the concentration the stronger the pattern that appears in the test paper. On the other hand fine differences can become lost in the complexity of form, and may be seen better when the sap is more diluted.
- Any concentration of a metalsalt reagent can be used. A 1% solution is generally strong enough, but of course can be changed for speacial reasons. Stronger solutions are not recommended for general use, and weaker ones tend to bring out less. A certain balance between the strength of sap and reagent should be found.
- Circular or horizontal pictures can be made. The liquids rise by means of a paper wick set in a small hole in the middle of the paper and spread outwards. This adaptation needs more space than the vertical form and a support for each paper. This method is not equally suitable for all cases. Plant saps often produce semicircular forms. These have room to develop unhindered in the width of the veritcal test, but become wedged shaped in the restricted centre space of the horizontal method.
The restricted center is very usefull on the pother hand when testing very diluted saps. It empahsis weak form and color bands without altering them.
The method described for the vertical test was used for all the experiments mentioned and illustrated in this work.
2. Fundamental Experiments: Plant, Reagents
Concerning the Time when Sap and reagent rise
The question whether it is more important whenthe sap or the reagent is set to rise in the paper is answered by the following experiment. Fresh plant saps were set to rise in four papers twice a day for some time. Two of each four tests were developed with the reagent twelve hours later. The two other papers, containing only the sap were stored in a dark cupboard. Three weeks after the last experiment in the series, all these unfinished tests were completed with the reagent at the same time.
Plate 28 shows a part of this experiment with the extract from iris germanica developed with gold chloride 1%. The plants were uprooted at the times stated and the sap set to rise shortly afterwards. The pictures in the top row were developed with the reagent at different times, in each case twelve hours after the sap had risen in the paper. The papers in the bottom row contain the same saps as those above them, but they were all developed at the same time as each other some weeks later.
The two rows are obviously similar. Unimportant differences are due to slight fermentation of the saps in the paper during the storage. This experiament, repeated several times during the last years with other plants and reagents always led to the same conclusion. The time when the reagent is added is not important provided the sap is dry in the paper. The plant itself determines the formation in the picture.
Concerning the Time the Plant is picked and the Time the sap is set to rise.
It must be found whether the time the plant is picked or the time the sap is set to rise in the paper is decisive for the test.
Double quantities of mistletoe were picked. Half was used for the daily pictures, the other half was put in a glass jar in the refrigerator at about 39(F. Twenty four hours later the sap was extracted and set to rise. The pictures were similar to those obtained the day before. The sap of the mistletoe that was still on the tree during those twenty four hours produced different pictures. The experiment was repeated daily forsome time with the same result. The time the plant is picked is decisive for the test, and determines the apperance of the picture obtained. This supports the findings of H. Kruger who examined plants saps with the copper-crystallisation method according to Pfeiffer. (Bibl. 18)
Tests that do not develop
There are times when some plant saps do not produce a picture at all, in spite of the usual conditions. Examples can be seen in Plate 7. It might be thought that the viscosity of the saps at such times prevents the reagent from rising, but this conjecture was disproved as far as the saps in question are concerned.
the viscosity of the saps was determined during a period when the reagent often failed to rise. No connection was found between the degree of viscosity and the failure of the reagent. It was found that the viscosity influences the height to which the sap rises, but not that reached by the reagent. The bottom line of test pictures in Plate 7 demonstrates this well. The most viscous sap obtained during the week was on July 27. This sap rose about half as high in the paper (as far as the base of the forms in the finished test) as those on the days before and after, yet it was the only one during those three days to develop into a well formed picture. The least viscous sap, the one that rose the highest in the paper was on July 29, yet on that day the reagent reached a lower comparative height than on any other day of the week.
It can also happen that at certian times some metalsalt solutions rise without difficulty to produce well developed pictures, whereas another used as reagent on the same sap may rise only partialy or not at all. An article on the special connection for example between sppper salt solutions and the sap of apple mistletoe may be published later.
Very often a 50% extract produces a fully developed picture, but diluted to only 10% fails to do so. It might be asked whether the sap must have a certain concentration in order to respond to the reagent. Experiments show that this is not the case. Whatever the physical process accompanying the failure may be, we can see the fact that a sap does not answer to the reagent as pointing to an abnormal condition of the formative power in the plant at the time it was picked. When the conditon is present, it can be graded by the stage of dilution of the sap at which it appears. For example:-
- When the 50% extract fails to develop the test, the formative forces in the sap are either absent or very repressed.
- When the 50% extract develops the test, but fails in 10% dilutuion, the condition is moderate.
- When the 50% extract develops the test, the 10% dilution does also, but the 5% fails, the condition is slight.
Saps viscous enough to form a crust that hinders the reagent, can be tested by the method described under the heading of "The Examination of Viscous Saps".
Concerning Silver Nitrate as Reagent
Increasing cencentrations of silver nitrate were compared in their effects as reagents to plants saps.
The same mistletoe extract was set to rise in severla papers. Each of these papers containing the same sap was developed with a differant concentration of silver nitrate.
The first experiment of this kind was made in 1954 in the range 0.5% to 32%. This was a time when the mistletoe needed silver nitrate about 8% to produce a picture equal in form value to 3% or even 2% some years later. The very strong concentrations were soon discontinued as they produced a complexity of form beyond any ever reached by a 1% solution. These strong concentrations however, gave the clue to two phenomena often noticed in the test pictures, wither separately or togeather. The pictures finished with the strong concentration in the series reproduced in Plates 11, 12, 13 have darkened too much to show these details but they can be studied in Plate 29 in four more recent test.
One of these characteristics is the wavy upper border where each waves contain infinitesimal smaller waves. Tiny forms proliferate whereever they find room to do so, making a second minature picture to crown the test. The weaker of the two picures at the top on the right shows these forms well, because they are not so numerous as usual, and have not merged into an outline. In some cases this becomes considerably darker than the rest of the test. In cases like the stronger picture at the top on the left they reamain drab colored and contrast well with the usual dark black-brown of the rest of the picture. This kind of outline is a sure sign of strong formative impulses in the sap.
The two pictures below illustrate the other distinctive feature of very strong formative power in the sap. It is usually hidden in dark color, but again two less strong test that have remained a lighter brown should serve to make the description clear. The characteristic referred to is the drawing, as if done with a fine pen, that appears in the lower part of the test, the part originally covered by the plant sap. The extent of this area for the picture on the right can be seen clearly. These drawings are always variations of the same form. They may be drawn and shaded in "light and dark" and appear then like tap roots extending downwards usually to the lower edge of the paper. They may be drawn form within form, giving an almost three dimensional effect. This can be seen well in plate 1. The greater the extent of the drawn surface the stronger the formative impulses in the sap. The partly risen test below on the left also shows signs of the proliferating upper border described above. Strong test display both these signs, and can be recognised however dark they have become.
Both characteristics can be obtained practically for certain with most plants if silver nitrate 30% to 40% is used as reagent. The picture becomes very dark green with grey/white drawing. It is interesting to observe such a picture "in action".
The reproduction of the Experiment
The reproduction of this experiment presents difficulties at forst sight unless certain facts are grasped. Each repetition begins with an unknown factor, namely the strength of the formative impulse in the sap on the day chosen. This reamins hidden until the picture is developed with silver nitrate 1%. It may be equal in form value to say 0.5%, or 2% or more, or anywhere between, and will affect the apperance of the whole series. Very numerous concentration series were made in the course of different months and years before sets of almost identical apperance were achived in the limited range of 0.5% to 2%. The important point to realise is, that even if every repetition does have a different apperance, the result is the same:- Increase in the concentration of the silver reagent always brings an increase in the strength or intensity of form in the pictures, as well as a progressive darkening of color.
The three series in Plates 11, 12, 13 illustrate this. They all look different from one another, but show a common trend from slighter forms and paler color to braoder, heavier forms with more detail and darker color, as described in the last paragraph.
Sliding Scales of Form Values
It might be objected that the pictures that are comparable to the experimental series with silver nitrate in increasing concentrations are chosen at random and are therefore worthless, being due to mere chance. A series of sliding scales show that this objection is not valid.
Practically every day for a month silver concentration series were made in the range 0.5%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, and 3%. This allowed a number of sliding scales to be built up, by which daily variations in the form values in the mistletoe tests could be accurately assessed. For instance: Three strengths of silver nitrate, 1%, 1.5%, and 3% were tried on mistletoe picked on 9.10.1958.
Three other strengths, 0.8%, 1%, and 2% were tried on the mistletoe of 10.10.1958.
The pictures of these two series turned out to be of equal value, in spite of the different strengths of silver nitrate used to develop them.
The pictures of:-
- 9.10 with 1% were similar to those of 10.10 with 0.8%.
- 9.10 with 1.5% were similar to those of 10.10 with 1%.
- 9.10 with 3% were similar to those of 10.10 with 2%.
This means that the misltetoe of 10.10 was stronger in itself and needed less silver than on 9.10 to develop a picture of equal form value.
In other cases the scale showed a decrease in form value from day to day. The experiments show one of the ways in which the kind of form and color wave referred to on page 19 passes into something new.
Concentration Series with Metals other than Silver
Several series were made at different times with:-
Gold chloride 0.5%, 1%, and 2%. Stronger solutions were not tried owing to the cost, but they proved unnecessary. The difference between 0.5% and 1% was not always marked, but 2% produced definatley less form, and changed the color to strong yellow.
Copper in various combinations. The strengths were from 0.5% up to 10%. Copper solutions as reagent cover the plant sap completly. The picure consistsof brownish green forms that hang down from the upper border into the plae green area of the test. Fine brown drawings distinguish the lower part. These decrease and disappear with increasing strengths of copper solutions.
Iron sulphate strengths 0.5% to 6%. Mercury bichloride, strengths 0.5% to 4%, about saturation point. Pictures with these solutions are similar in form but different in color from the copper tests. Increasing concentrations of both these metalsalts lead to decreased drawing and simplify the result.
In the case of all these metalsalts, increase in the concentration of the solution used decreases the form that appears in the test.
The special quality of Silver as reagent
Silver as reagent occupies a very special posigtion among all the metals tried. In contrast to them, silver uder in increasing concentration produces increasing formation in the test pictures. This fact can be followed up to saturation of the silver solution at about 56%. Silver has an affinity to form L. Kolisko found this same quality of silver when using capillary-dynamolysis to test the reaction of solutions of silver nitrate at various times. (Bibl.4)
The Formation in Pictures developed with Gold Chloride as Reagent
It is the plant sap itself, that brought to expression in the test picture with silver nitrate as reagent, shows sometimes weaker, sometimes stronger formative power, giving the impression that sometimes weaker, sometimes stronger silver solutions had been used. The formative power present in plant saps is able to express itself in test pictures developed with other metalsalts, particualry gold chloride. These other metalssalts that have no affinity to form themselves, should not be used stronger than 1% or they begin to overpower the plant. Because it is dificult to reproduce adequately pictures developed with silver nitrate that have become very dark in color, it must be shown how these compare with the duplicate pictures of the same saps developed with gold chloride.
Plate 30 shows pairs of duplicate picturesmade from the sap of mistletoe picked on five different ocassions. Each sap was examined in two papers, one with gold chloride, one with silver nitrate.
The pictures in the top row were finished with silver nitrate 1%. Each picture in the lower row wasmmade from the same sap as the picture diretly above it, but in this case the reagent was gold chloride 1%.
It is evident from these examples that the plant is able to express its formative power to a high degree with gold chloride as reagent. This is sufficent for the purpose of this work, and allows the interchange of the so-called gold and silver picutres for the illustratons.
Capillary Dynamic Test
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