REMARKS ON THE STRUCTURE OF FIBRE. 261 



appearance the first links of this intricate chain will be wanting, and 

 the ingenious superstructure, without cohesion. 



Dr. Barry is of opinion, that muscle is nothing more than a " vast 

 bundle of spirals ;" and that the muscular fibres and ultimate fibrillse, 

 are all composed in a similar way, of various sized, interlaced, double 

 spirals ; and it is here that we would recall his remark, as given above, 

 relative to the oblique direction of the line separating the apparent seg- 

 ments in the small filaments, in connection with the oblique direction 

 of the spaces between the curves of the spiral threads in his larger 

 figure. For if it can be shown, as it readily can be, that the transverse 

 lines, though comparatively some distance apart in the ultimate muscular 

 fibrillae, of the salmon for instance, are strictly transverse, and circum- 

 scribe truly rectangular spaces, as represented rudely in 

 this figure, and that the most careful adjustment of focus, 

 will not show any diagonal lines connecting these transverse 

 ones, how can such an appearance be explained upon the 

 double spiral principle ? 



The same argument, perhaps, will not hold with regard to 

 the transverse striae of a whole muscular fibre, as it would 

 be difficult to ascertain accurately whether they were or 

 were not more or less oblique, as in fact they often are, not, 

 in our opinion, from their being portions of a spiral, but owing to other 

 causes, such as more or less irregularity in the degree of contraction of 

 the ultimate fibrillse, on different sides of the fasciculus, by the allocation 

 of the constituent particles, of which fibrillse the transverse striae are 

 formed ; or by the mechanical traction of them, in the preparation of 

 the tissue for microscopical examination ; or in the pressure to which 

 it may be subjected between the glasses. 



Any one of these causes (or perhaps others might be assigned), are 

 sufficient to produce more or less obliquity in the direction of the trans- 

 verse trise on the muscular fasciculus ; and the two latter would suf- 

 fice to produce the same obliquity in the transverse lines of an ultimate 

 fibrilla, where such obliquity, as it often happens, is observable. We 

 have not alluded at present to the existence of a spiral filament (not Dr. 

 Barry's), in or upon the ssercolemma of the muscular fasciculi, of which 

 an excellent observer of our acquaintance, is, we believe, satisfied, as the 

 consideration of it is remote from our present object. Some obscurities, 

 perhaps, still hang over the structure of muscle ; but, in Mr. Bowman's 

 views on this subject we most fully concur, believing that they repre- 

 sent, as nearly as our present means of microscopic observation will 

 allow, the truth in this vcxata questio. 



