The first serious attack of the velocipede epidemic in this country set in during the closing weeks of winter, It raged with great violence during the spring; but the hot weather, which seems to favor other epidemics, threw cold water on this, and by the middle of July a velocipede was rarely seen in our streets. Just as we began to turn our two-wheeled steeds out to grass, the British Empire awoke to find the fever upon it. No quarantine regulations or sanitary precautious had sufficed to ward off the attack. High and low, rich and poor, were seized with such a rage for velocipede exercise, that even the grayest engineering periodicals and papers felt themselves obliged to say something on the subject . Engineering and the Engineer held off as long as possible, but were obliged to give in finally to the popular furore. Engineering, at the outset, made some remarks upon the extent of the popular demand for velocipedes, but dropped the subject almost immediately. Another mechanical journal copied in full our editorial on the " Mechanics of Walking," and forgot to credit it. A London book compiler also appropriated it. The Engineer compromised matters by getting Professor J. Macquorn Rankine to write a series of recondite mathematical articles on the gay velocipede, with formul long enough for a velocipede course, and numerous enough to accommodate all the velocipedes in England. To discuss the topic in any other style than this, would have been beneath the dignity of this journal, which is nothing if not scientific. Nevertheless, we arc willing to admit that the keen analysis of Professor Bankine has evolved sub tile points of philosophy from the bones and marrow of our pet, that make us more in love with it than over. While our feet are moving in lively and exhilarating motion, our mind may now also be actively employed in meditating upon the "deflection of the base track, " which is expressed by the neat little formula : PM= mPv2 but out of which issue forth an g.cm army of' sines, cosines, tangents, and logarithms. We may reduce " the effect of (our) unskillfulness upon oscillations," into a triple equation of the second degree, and correct our "horizontal oscillations" by the application of the formula ?11 which Professor Rankine has so kindly bestowed upon v p mankind, and which once stored up in the head of a velocipede rider will forever effectually prevent a loss of balance in his body, whatever may be the effect upon his brain. Could we have had Professor Rankine's formulre to guide s at the outset of our velocipede experience, how many umps and bruises we might have spared ourselves. How sy it would:have been when we found ourselves sprawling nd with painful effort e:l(:tri()ated ourselves, vainly endeavoring ing to exhibit no sign of discomfiture, to have avoided such humiliating defeat by such an adjustment of our co-sines, as would have prevented our flying off in a tangent to tho "ar of progression." Truly, as Solomon averred, "wisdom is pro fitable to direct." But while the velocipede has been doiug so much in Eng land, it has been recuperating itself for a fresh run in America and we already see many of these machines in active opera tion on smooth pavements not yet opened to travel for larger vehicles. The velocipede is not dead, but will, this cool and delightful autumn weather, once more resume its sway though to what extent it may conquer is yet to be recorded in history.