C. F. Keil and Franz Delitzsch on 2 Chronicles 26:15

2Ch 26:15

Besides this, he provided Jerusalem with machines for defence on the towers and battlements. חשּׁבנות from השּׁבון, literally excogitata, i.e., machinae, with the addition “invention of the artificers,” are ingenious machines, and as we learn from the following וגו לירוא, slinging machines, similar or corresponding to the catapultae and ballistae of the Romans, by which arrows were shot and great stones propelled. Thus his name spread far abroad (cf. 2Ch 26:8), for he was marvellously helped till he was strong.Uzziah’s pride, and chastisement by leprosy. His death and burial. - The fact that the Lord smote Uzziah with leprosy, which continued until his death, so that he was compelled to dwell in a hospital, and to allow his son Jotham to conduct the government, is narrated also in 2Ki 15:5; but the cause of this punishment inflicted on him by God is stated only in our verses.