September 15, 1893.] 



SCIENCE. 



149 



lated from outside the metal case. To avoid any ill 

 effects that might be caused by difEerences in the internal 

 and external pressure when the apparatus is sunk in deep 

 water, a kind of balloon filled with air is connected with 

 it. As the pressure increases, in descending, the balloon 

 is compressed, extra air is thus forced into the box, and 

 the jjressure on its walls equalized. A stout foot to 

 supjjort the apparatus and weights to sink it comjjlete it 

 for practical purposes. 



In water near the shore, not greatly exceeding one 

 metre in depth, the apparatus can be conveniently fixed, 

 without the operator needing to enter the water, and, by 

 direct sunlight, good negatives can be obtained in ten 

 minutes. When the water is deeper the operator must 

 descend in diving costume to fix the case securely on its 

 stand before commencing the actual work of photography. 

 In calm, bright weather j)hotographs can then be ob- 

 tained by direct sunlight in from thirty to fifty minutes. 

 Colored glasses, preferably blue, must be interposed be- 

 tween the objective and the water, in order to obtain 

 sharp images. 



By the use of artificial light to illuminate the sur- 

 roundings, however, matters are still more simplified. To 

 this end, M. Boutan has contrived a special magnesium 

 lamp. A cask of two hundred litres capacity is filled 

 with oxygen gas, and on its ujjper end is fixed a spirit 

 lamp, which is covered by a bell glass. A vessel contain- 

 ing magnesium, in powder, is connected with this lamp 

 in such a manner that the metal can be projected across 

 the flame by the action of a rubber ball which serves as 

 bellows. The oxygen gas, of course, is intended to assist 

 combustion, and the lamp, having been lighted and cov- 

 ered by its protecting globe, the cask simply requires 

 weighting to sink it. 



Good instantaneous negatives have thus been obtained 

 by M. Boutan during a violent storm, when no daylight 

 could penetrate the depths. They are lacking, as regards 

 background, but this he attributes to imperfections in the 

 apparatus, particularly the objective. He also found it 

 necessary to place before the lens a diaphragm of very 

 small aperture to secure a sufficient degree of sharpness. 

 If a formula were calcidated for an objective, the front of 

 which might be exposed to sea water, he thinks these 

 drawbacks might be remedied. 



As it is, he has proved that photographs can be taken 

 in a brief time under water, in calm weather, by direct 

 sunlight, at depths up to six or seven metres; whilst, by 

 the use of his si^ecial lamp, they can be taken, instanta- 

 neously, at any dejDth that can be conveniently reached by 

 a diver, and the state of the weather is of no importance. 



THE SCIENTIFIC BASIS OP COMPOSITION. 



BY DR. CHABLES H. J. DOUGLAS, BOYS' HIGH SCHOOL, BROOKLYN. 



The end of literary composition is effective communi- 

 cation. To this end there are necessary, first, something 

 to communicate and, second, some means of communica- 

 tion. The only thing to be communicated is thought. 

 The medium of communication is language. One cannot, 

 then, expect to understand the philosophy of literary 

 composition without investigating both the nature and 

 the process of handling both thought and language. 



Psychologists recognize three distinct kinds of thought, 

 viz., the concept, the judgment and the argument. The 

 concept, the simplest form of thought, may be defined as 

 the act of mind by which we merely become aware of 

 somethkig. Objectively considered, the concept is indi- 

 visible and unrelated — a kind of intellectual atom. The 

 simple judgment, a more complex form of thought than 

 the concept, may be defined as the act of mind by which 

 we apprehend an agreement or disagreement between two 



concepts. Objectively considered, the judgment is a 

 complex unit, resolvable into its constituent parts — a kind 

 of intellectual molecule. 



The argument, the most complex form of thought, is 

 commonly regarded as differing essentially from both 

 the concept and the judgment. It is, however, in the last 

 analysis, nothing else than a comj)lex judgment. It may 

 be defined as the act of mind by which we apprehend an 

 agreement or a disagreement between two concepts, by 

 apprehending an agreement or a disagreement between 

 each of them and a third concej)t. 



The relation of logic to composition is peculiar and 

 quite likely to be misapprehended. The formation of 

 judgments upon a subject must, of course, precede the 

 communication of thought upon that subject. But the 

 formation of judgments upon a subject is nothing else 

 than the study of that subject; it is not composition. 

 That jsrocess begins with the selection of judgments al- 

 ready formed; and it ends, so far as the handling of 

 thought is concerned, with the arrangement of them ac- 

 cording to a certain recognized principle. 



At this jDoiiit, then, the mind begins a new process. 

 Ceasing, for the moment, to form judgments about the 

 subject of the communication, it begins to form judg- 

 ments about those judgments in order to the process of 

 discourse. This may be defined as the selection and the 

 arrangement of judgments with a view to the greatest 

 mental effect in apprehending them. 



Thus, while the formation of a set of judgments about 

 the subject of the communication, and of another set of 

 judgments about the first set, are both processes implied 

 by the process of composition, neither of them is included 

 in that process. Again, the mind, in the formation of 

 judgments about its own judgments, in order to dis- 

 course, is subject to the laws of logic no less than it is in 

 the formation of judgments about the subject of the 

 communication. The relation of logic to composition is, 

 therefore, seen to be both vital and complex. 



But, while the mind in the formation of judgments 

 about its own judgments, in order to discourse, is subject 

 to the laws of logic, yet the principles according to which 

 the selection and the arrangement of the judgments are 

 made, are not principles of logic, but of dialectic. This 

 may be defined as the science of effective thought, as 

 logic is the science of correct thought. 



So imjDortant are the selection and the arrangement of 

 judgments in the effective handling of thought, that it 

 has sometimes been said that what the judgment is to the 

 concept, and what the argument is to the judgment, such 

 is method to the argument; and that, consequently, a 

 fourth division is necessary to comj)lete the doctrine of 

 logic. Both the premise and the conclusion of this state- 

 ment are, however, untenable. 



It is evident that method does not sustain the same re- 

 lation to the argument that the argument does to the 

 judgment and that the judgment does to the concept, 

 first, because the argument does not sustain the same re- 

 lation to the judgment that the judgment does to the 

 concept; and, second, because method is of precisely as 

 much importance in simple discourse, where there are no 

 arguments at all, as it is in reasoning, where there is 

 nothing except arguments. 



The importance of method, instead of arising fi-om 

 some relation which it is supposed to sustain to the argu- 

 ment, dejieuds entirely ujjon the principle of the economv 

 of the recipient's attention. By selection, the waste of 

 his energy in the formation of irrelevant or unimportant 

 judgments is avoided. By arrangement, the greater sus- 

 cei^tibility of his mind at certain jDoints in the time-series 

 of cognitions which he makes, and to certain sequences of 

 judgments, is taken advantage of. 



